{"id":"https://data.mapsnap.org/runs/v1.3/iiif/chronoscope/sanborn01790_105.main.iiif.json","type":"AnnotationPage","@context":["http://www.w3.org/ns/anno.jsonld"],"label":"Chicago, Illinois | 1950 | mapsnap generated fit (2026-09-21)","creator":{"type":"Software","name":"mapsnap","homepage":"https://mapsnap.org"},"rights":"https://opendatacommons.org/licenses/odbl/1-0/","metadata":[{"label":"generated","value":"2026-09-21"},{"label":"run","value":"corpus-v1"},{"label":"pages","value":"139"},{"label":"placed","value":"107"},{"label":"unplaced","value":"32"},{"label":"fit sources","value":"georef-snap 69, georef 33, snap:0 3, georef-street 2"},{"label":"key map","value":"georeferenced"},{"label":"split sheets","value":"3 sheet(s) cut into 7 panels"},{"label":"unplaced pages","value":"p0__1 (tier 4, 41.89100,-87.75063 +/-2843m); p0__2 (tier 4, 41.89100,-87.75063 +/-2843m); p0__3 (tier 4, 41.89100,-87.75063 +/-2843m); p102 (tier 1, 41.90973,-87.77276 +/-200m); p103 (tier 4, 41.89100,-87.75063 +/-2843m); p104 (tier 4, 41.89100,-87.75063 +/-2843m); p105 (tier 2, 41.87933,-87.75838 +/-102m); p107 (tier 2, 41.87937,-87.75510 +/-102m); p108 (tier 1, 41.87944,-87.75024 +/-264m); p110 (tier 1, 41.89058,-87.75674 +/-250m); p111__1 (tier 4, 41.89100,-87.75063 +/-2843m); p111__2 (tier 4, 41.89100,-87.75063 +/-2843m); p112 (tier 1, 41.89471,-87.77365 +/-268m); p117 (tier 2, 41.88062,-87.72790 +/-100m); p118 (tier 1, 41.90582,-87.77255 +/-275m); p119 (tier 4, 41.89100,-87.75063 +/-2843m); p11__2 (tier 1, 41.89882,-87.74362 +/-100m); p120 (tier 4, 41.89100,-87.75063 +/-2843m); p121 (tier 4, 41.89100,-87.75063 +/-2843m); p122 (tier 2, 41.89787,-87.73925 +/-100m); p124 (tier 2, 41.89613,-87.73602 +/-100m); p125 (tier 4, 41.89100,-87.75063 +/-2843m); p126 (tier 1, 41.89685,-87.74528 +/-261m); p128 (tier 1, 41.89317,-87.74463 +/-256m); p129 (tier 4, 41.89100,-87.75063 +/-2843m); p130 (tier 2, 41.87780,-87.73648 +/-100m); p131 (tier 2, 41.87782,-87.73410 +/-100m); p132 (tier 4, 41.89100,-87.75063 +/-2843m); p133 (tier 2, 41.87788,-87.72927 +/-100m); p134 (tier 4, 41.89100,-87.75063 +/-2843m); p51 (tier 1, 41.89154,-87.73660 +/-258m); p52 (tier 2, 41.89168,-87.72968 +/-453m)"}],"items":[{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0001/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p1","metadata":[{"label":"streets","value":"5"},{"label":"intersections","value":"6"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0001/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0001","type":"ImageService3","width":1464,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1464.0,0.0 1464.0,2078.6 1254.2,2077.3 1254.7,2015.3 -0.0,2009.2 -0.0,-0.0 1464.0,0.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0001/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[134.0,2071.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7752453,41.8983626]}},{"type":"Feature","properties":{"resourceCoords":[134.0,79.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7753618,41.9019941]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0010/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p10","metadata":[{"label":"streets","value":"5"},{"label":"intersections","value":"4"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0010/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0010","type":"ImageService3","width":1458,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"254.1,2082.0 253.9,0.0 1257.3,13.5 1255.2,2085.1 254.1,2082.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0010/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[254.0,1588.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7483601,41.8995647]}},{"type":"Feature","properties":{"resourceCoords":[254.0,1076.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7483799,41.9004937]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0100/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p100","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0100/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0100","type":"ImageService3","width":1468,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"434.5,2126.0 435.1,2091.3 248.8,2087.5 277.7,0.0 1468.0,0.0 1468.0,2126.0 434.5,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0100/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.72894372094646,41.88465616591348]}},{"type":"Feature","properties":{"resourceCoords":[1468.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.72517989606384,41.88476034233264]}},{"type":"Feature","properties":{"resourceCoords":[1468.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.72497867209206,41.88067344689258]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.72874249697469,41.88056927047342]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0101/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p101","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0101/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0101","type":"ImageService3","width":1462,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,2126.0 -0.0,-0.0 1462.0,0.0 1462.0,2126.0 -0.0,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0101/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7753360576515,41.91120094961304]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77261658812135,41.91120994259612]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77259913907479,41.90824614837498]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77531860860493,41.908237155391895]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0106/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p106","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0106/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0106","type":"ImageService3","width":1464,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,2126.0 -0.0,513.3 1439.2,511.9 1464.0,554.3 1464.0,2126.0 -0.0,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0106/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75861039957694,41.881313217660285]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75501639674715,41.88135308418854]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75493918382305,41.87743980170463]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75853318665284,41.87739993517638]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0109/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p109","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0109/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0109","type":"ImageService3","width":1457,"height":2127},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,2127.0 -0.0,506.4 1410.0,515.2 1410.4,550.4 1457.0,550.7 1457.0,2127.0 -0.0,2127.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0109/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74874962186794,41.88141670667262]}},{"type":"Feature","properties":{"resourceCoords":[1457.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74518691948452,41.881477293661746]}},{"type":"Feature","properties":{"resourceCoords":[1457.0,2127.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74506895617458,41.877577623806324]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2127.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.748631658558,41.877517036817196]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0113/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p113","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0113/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0113","type":"ImageService3","width":1449,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1225.8,570.1 1227.3,2126.0 -0.0,2126.0 -0.0,558.9 1225.8,570.1\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0113/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73845501284774,41.881543817716484]}},{"type":"Feature","properties":{"resourceCoords":[1449.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73496427220236,41.88161075739905]}},{"type":"Feature","properties":{"resourceCoords":[1449.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73483328180654,41.877770577885435]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73832402245192,41.87770363820287]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0114/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p114","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0114/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0114","type":"ImageService3","width":1464,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"252.1,559.0 1260.3,562.2 1271.0,2126.0 262.8,2104.1 252.1,559.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0114/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.736104674299,41.881578398332266]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73255294607299,41.88163038721133]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73245225434053,41.877763150693035]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73600398256654,41.87771116181397]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0115/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p115","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0115/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0115","type":"ImageService3","width":1452,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"981.9,2126.0 241.2,2126.0 232.2,554.7 985.3,561.7 981.9,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0115/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73360945114881,41.88160400350452]}},{"type":"Feature","properties":{"resourceCoords":[1452.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73010041421134,41.881658246781086]}},{"type":"Feature","properties":{"resourceCoords":[1452.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.72999448807606,41.87780591205733]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73350352501353,41.87775166878077]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0116/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p116","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0116/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0116","type":"ImageService3","width":1464,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1464.0,2126.0 -0.0,2126.0 -0.0,553.4 1464.0,556.3 1464.0,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0116/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73122520179534,41.88163475195961]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.72765506387779,41.88168407252933]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.72755954041438,41.87779677855764]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73112967833192,41.877747457987915]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0011__1/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p11 [1]","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"5"},{"label":"split_canvas_x","value":"0.0"},{"label":"split_canvas_y","value":"0.0"},{"label":"split_canvas_w","value":"5900.0"},{"label":"split_canvas_h","value":"8504.0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0011__1/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0011","type":"ImageService3","width":1475,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"248.0,2062.0 800.4,2057.6 803.0,2007.4 858.5,1915.8 1029.5,1913.9 1113.7,2055.0 1475.0,2052.1 1475.0,0.0 247.6,0.0 248.0,2062.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0011__1/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[248.0,558.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7459541,41.9014332]}},{"type":"Feature","properties":{"resourceCoords":[248.0,2062.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7459001,41.8986915]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0012/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p12","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0012/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0012","type":"ImageService3","width":1458,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"128.7,2077.7 122.2,30.1 -0.0,30.5 -0.0,-0.0 664.0,1.7 664.6,66.7 1386.3,60.1 1402.0,2063.7 1037.2,2067.7 128.7,2077.7\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0012/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74326760139078,41.90253569779194]}},{"type":"Feature","properties":{"resourceCoords":[1458.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73971353728615,41.90256654093922]}},{"type":"Feature","properties":{"resourceCoords":[1458.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73965353593928,41.89868204727214]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74320760004392,41.89865120412486]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0123/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p123","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0123/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0123","type":"ImageService3","width":1459,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"362.9,2097.3 371.5,31.1 1411.7,31.8 1402.8,2097.1 1459.0,2126.0 362.9,2097.3\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0123/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73939134965141,41.89885641418443]}},{"type":"Feature","properties":{"resourceCoords":[1459.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73592919376749,41.89891687670194]}},{"type":"Feature","properties":{"resourceCoords":[1459.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73581166087219,41.895135156912254]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73927381675611,41.895074694394744]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0127/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p127","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0127/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0127","type":"ImageService3","width":1459,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"262.9,1048.6 266.5,516.3 270.4,26.9 1219.4,30.2 1203.6,2074.1 261.6,2060.7 262.9,1048.6\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0127/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74651208627974,41.89689221929019]}},{"type":"Feature","properties":{"resourceCoords":[1459.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74298788437288,41.89696679754036]}},{"type":"Feature","properties":{"resourceCoords":[1459.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74284291427577,41.89311724299299]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74636711618263,41.89304266474282]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0013/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p13","metadata":[{"label":"streets","value":"7"},{"label":"intersections","value":"12"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0013/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0013","type":"ImageService3","width":1475,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"719.0,64.1 -0.0,65.2 -0.0,-0.0 1475.0,0.0 1475.0,62.3 1244.0,62.9 1243.7,2072.1 719.1,2073.9 719.0,64.1\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0013/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[719.0,1064.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7398395,41.900635]}},{"type":"Feature","properties":{"resourceCoords":[719.0,564.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.739863,41.9015447]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0014/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p14","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0014/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0014","type":"ImageService3","width":1461,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1256.2,2067.9 238.8,2075.8 229.9,63.8 462.9,62.1 462.7,0.0 1016.2,15.2 1016.4,58.2 1242.5,56.5 1256.2,2067.9\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0014/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73916242045809,41.90258570224174]}},{"type":"Feature","properties":{"resourceCoords":[1461.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73561709743136,41.90262512792203]}},{"type":"Feature","properties":{"resourceCoords":[1461.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73554055743975,41.89875814115904]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73908588046648,41.89871871547875]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0015/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p15","metadata":[{"label":"streets","value":"7"},{"label":"intersections","value":"12"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0015/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0015","type":"ImageService3","width":1489,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1254.8,2080.0 235.1,2084.9 227.9,42.7 -0.0,43.6 -0.0,-0.0 1249.7,0.0 1254.8,2080.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0015/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1254.0,1567.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.733611,41.8998189]}},{"type":"Feature","properties":{"resourceCoords":[230.0,552.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7361183,41.9016041]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0016/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p16","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0016/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0016","type":"ImageService3","width":1453,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1244.1,0.0 1233.4,2072.5 210.4,2069.8 220.2,0.0 1244.1,0.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0016/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73422109374759,41.90264047230908]}},{"type":"Feature","properties":{"resourceCoords":[1453.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7307089092404,41.90270720682593]}},{"type":"Feature","properties":{"resourceCoords":[1453.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73057863915247,41.898855276447875]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73409082365966,41.898788541931026]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0017/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p17","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0017/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0017","type":"ImageService3","width":1489,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"258.3,2069.3 258.0,1.4 1269.5,0.0 1274.2,2066.6 258.3,2069.3\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0017/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73183904431197,41.902690862258396]}},{"type":"Feature","properties":{"resourceCoords":[1489.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.72823128293776,41.90274501690099]}},{"type":"Feature","properties":{"resourceCoords":[1489.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.72812812532989,41.898883931917204]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7317358867041,41.898829777274614]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0018/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p18","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0018/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0018","type":"ImageService3","width":1453,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"241.6,2069.4 232.6,7.5 1453.0,0.0 1453.0,2065.8 241.6,2069.4\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0018/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7293293200502,41.90274861511675]}},{"type":"Feature","properties":{"resourceCoords":[1453.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.72579548978928,41.90279612856057]}},{"type":"Feature","properties":{"resourceCoords":[1453.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7257027403071,41.898920465683354]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.72923657056802,41.898872952239536]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0019/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p19","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0019/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0019","type":"ImageService3","width":1484,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,-0.0 16.1,61.3 15.8,0.0 1282.2,0.0 1282.1,62.2 1319.1,62.2 1327.8,2069.1 13.9,2066.5 -0.0,2126.0 -0.0,-0.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0019/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7756154059231,41.898468872149465]}},{"type":"Feature","properties":{"resourceCoords":[1484.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77201357918912,41.89851992093004]}},{"type":"Feature","properties":{"resourceCoords":[1484.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77191601668838,41.89465194302732]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77551784342236,41.89460089424674]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0002/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p2","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0002/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0002","type":"ImageService3","width":1473,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"213.8,2088.3 199.7,0.0 1370.5,23.7 1386.3,2087.4 213.8,2088.3\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0002/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77258744531092,41.902162976187775]}},{"type":"Feature","properties":{"resourceCoords":[1473.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76904644539931,41.90220884392656]}},{"type":"Feature","properties":{"resourceCoords":[1473.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76895812498144,41.898378011472786]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77249912489305,41.898332143734]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0020/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p20","metadata":[{"label":"streets","value":"8"},{"label":"intersections","value":"14"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0020/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0020","type":"ImageService3","width":1453,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1391.9,2070.2 57.2,2065.7 56.9,54.7 1386.4,61.0 1391.9,2070.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0020/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[57.0,560.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7723825,41.8974827]}},{"type":"Feature","properties":{"resourceCoords":[1388.0,1065.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.769108,41.8966223]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0021/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p21","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0021/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0021","type":"ImageService3","width":1484,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"255.5,2072.0 267.4,57.5 1275.8,71.4 1252.4,2084.7 255.5,2072.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0021/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76981834569396,41.89853364568155]}},{"type":"Feature","properties":{"resourceCoords":[1484.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76623452676353,41.89861912193753]}},{"type":"Feature","properties":{"resourceCoords":[1484.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76607116674762,41.89477050664131]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76965498567806,41.89468503038533]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0022/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p22","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0022/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0022","type":"ImageService3","width":1457,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1341.5,67.8 1360.7,2083.7 84.3,2081.1 79.1,65.0 1341.5,67.8\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0022/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76692538673407,41.898592921873714]}},{"type":"Feature","properties":{"resourceCoords":[1457.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76341012249736,41.89863936090487]}},{"type":"Feature","properties":{"resourceCoords":[1457.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76331972508382,41.894794394596296]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76683498932053,41.89474795556514]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0023/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p23","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0023/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0023","type":"ImageService3","width":1484,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1353.6,73.2 1358.1,2093.6 151.2,2076.6 144.8,60.3 1353.6,73.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0023/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76403877390278,41.898615818580325]}},{"type":"Feature","properties":{"resourceCoords":[1484.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76045951658435,41.89868023083327]}},{"type":"Feature","properties":{"resourceCoords":[1484.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76033641399533,41.89483650021691]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76391567131377,41.894772087963965]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0024/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p24","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"9"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0024/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0024","type":"ImageService3","width":1457,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1303.2,1071.9 1303.5,2068.5 92.1,2055.2 82.2,63.2 1457.0,73.4 1457.0,1073.5 1303.2,1071.9\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0024/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[624.0,1065.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.759383,41.8967261]}},{"type":"Feature","properties":{"resourceCoords":[624.0,2061.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7593312,41.8948996]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0025/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p25","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0025/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0025","type":"ImageService3","width":1484,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1355.2,2081.8 -0.0,2074.0 -0.0,1065.5 156.8,1067.2 157.1,55.1 1363.5,64.8 1355.2,2081.8\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0025/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75776495958915,41.89867045835158]}},{"type":"Feature","properties":{"resourceCoords":[1484.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75417751083548,41.89872849272541]}},{"type":"Feature","properties":{"resourceCoords":[1484.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75406659738726,41.89487596724363]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75765404614094,41.8948179328698]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0026/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p26","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0026/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0026","type":"ImageService3","width":1457,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1124.7,2070.7 117.8,2066.6 104.8,62.0 1234.4,59.2 1241.5,2039.9 1124.7,2070.7\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0026/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7547220273907,41.898717389377225]}},{"type":"Feature","properties":{"resourceCoords":[1457.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75117753347155,41.898746564744954]}},{"type":"Feature","properties":{"resourceCoords":[1457.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75112074114078,41.89486963171991]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75466523505993,41.89484045635218]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0027/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p27","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0027/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0027","type":"ImageService3","width":1487,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,2043.6 -0.0,46.2 1399.7,47.6 1403.4,2126.0 390.8,2126.0 390.1,2076.8 -0.0,2043.6\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0027/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75171901033124,41.89871771355218]}},{"type":"Feature","properties":{"resourceCoords":[1487.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7481319040839,41.8987567780807]}},{"type":"Feature","properties":{"resourceCoords":[1487.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7480573957676,41.89491239496473]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75164450201494,41.894873330436205]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0028/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p28","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0028/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0028","type":"ImageService3","width":1457,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1236.3,2074.0 231.6,2063.9 238.1,56.5 1236.5,63.2 1236.3,2074.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0028/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74892555029815,41.89876354006715]}},{"type":"Feature","properties":{"resourceCoords":[1457.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74536391988771,41.89881505678229]}},{"type":"Feature","properties":{"resourceCoords":[1457.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74526363813682,41.89491938353498]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74882526854726,41.894867866819844]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0029/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p29","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0029/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0029","type":"ImageService3","width":1487,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"280.1,1547.2 277.8,1060.0 275.8,51.9 1224.1,45.2 1222.4,1051.3 1220.7,2068.9 283.2,2077.1 280.1,1547.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0029/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74657144207556,41.898778088337885]}},{"type":"Feature","properties":{"resourceCoords":[1487.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74296211710232,41.898820178905346]}},{"type":"Feature","properties":{"resourceCoords":[1487.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74288183710192,41.894951987241406]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74649116207516,41.894909896673944]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0003/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p3","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0003/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0003","type":"ImageService3","width":1464,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"118.7,2042.5 120.0,0.0 1464.0,0.0 1464.0,47.5 1464.0,47.5 1464.0,2053.3 118.7,2042.5\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0003/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76958339878495,41.90215739622569]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76602800820436,41.90222560091003]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76589586964367,41.89835555322941]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76945126022426,41.89828734854507]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0030/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p30","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"6"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0030/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0030","type":"ImageService3","width":1462,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"264.0,2082.2 264.0,51.3 1462.0,40.7 1462.0,2066.3 264.0,2082.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0030/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[264.0,1061.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7435646,41.8968998]}},{"type":"Feature","properties":{"resourceCoords":[264.0,562.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7435814,41.8978045]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0031/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p31","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0031/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0031","type":"ImageService3","width":1487,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1263.0,64.6 1252.0,2065.4 1487.0,2065.7 1487.0,2126.0 458.6,2126.0 458.6,2062.0 354.9,2061.5 376.3,62.8 1263.0,64.6\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0031/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74160691027133,41.89887792384853]}},{"type":"Feature","properties":{"resourceCoords":[1487.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73796297228846,41.898945261663286]}},{"type":"Feature","properties":{"resourceCoords":[1487.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73783453752084,41.89503998348557]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74147847550371,41.89497264567081]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0032/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p32","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0032/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0032","type":"ImageService3","width":1462,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"0.0,2126.0 0.0,0.0 1462.0,0.0 1462.0,2126.0 0.0,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0032/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73905865560863,41.89892675689885]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73549725761315,41.898987383843014]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73537964528735,41.89510529808181]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73894104328284,41.89504467113765]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0033/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p33","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0033/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0033","type":"ImageService3","width":1472,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1014.3,62.5 1013.4,2126.0 276.2,2107.6 221.3,2079.2 235.2,60.0 1014.3,62.5\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0033/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73661424189837,41.898956430806095]}},{"type":"Feature","properties":{"resourceCoords":[1472.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73304178329464,41.89902568992664]}},{"type":"Feature","properties":{"resourceCoords":[1472.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73290833781935,41.8951580037779]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73648079642308,41.89508874465736]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0034/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p34","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0034/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0034","type":"ImageService3","width":1462,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,65.6 1246.9,68.9 1236.5,2075.8 1462.0,2075.8 1462.0,2126.0 -0.0,2126.0 -0.0,65.6\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0034/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73415264912514,41.899010095532454]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73059322724016,41.89907786413337]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7304617604208,41.89519793668024]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73402118230577,41.895130168079326]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0035/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p35","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0035/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0035","type":"ImageService3","width":1472,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1000.4,2071.1 1000.4,2126.0 458.1,2123.1 457.9,2072.8 232.0,2073.6 236.1,63.8 1248.4,63.4 1248.5,2070.2 1000.4,2071.1\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0035/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73169020171372,41.899048872239355]}},{"type":"Feature","properties":{"resourceCoords":[1472.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.72811119575253,41.89910849880581]}},{"type":"Feature","properties":{"resourceCoords":[1472.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.72799630965683,41.89523373126353]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73157531561802,41.89517410469708]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0036/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p36","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"9"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0036/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0036","type":"ImageService3","width":1462,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"245.3,52.7 1450.6,53.1 1462.0,0.0 1462.0,2126.0 -0.0,2126.0 -0.0,2064.2 246.8,2063.1 245.3,52.7\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0036/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[750.0,2061.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7273128,41.8953498]}},{"type":"Feature","properties":{"resourceCoords":[750.0,52.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.727418,41.899005]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0037/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p37","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0037/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0037","type":"ImageService3","width":1464,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"137.9,2077.6 137.7,2126.0 -0.0,2126.0 -0.0,40.1 1198.5,54.2 1174.8,2093.5 137.9,2077.6\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0037/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77548958063414,41.894782620486275]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7719345641884,41.89485933192052]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77178596183488,41.89098924787981]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77534097828062,41.89091253644556]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0038/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p38","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0038/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0038","type":"ImageService3","width":1464,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,2075.8 -0.0,40.4 1464.0,37.4 1464.0,2081.2 -0.0,2075.8\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0038/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77257715218958,41.89482030746283]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76901419704015,41.8948660557357]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76892557532297,41.890987328280424]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7724885304724,41.890941580007556]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0039/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p39","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0039/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0039","type":"ImageService3","width":1464,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1262.2,2086.6 279.2,2070.4 305.2,33.5 1279.5,44.0 1262.2,2086.6\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0039/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76976023975466,41.89484241349331]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76618651578018,41.894922523878115]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76603132908818,41.89103207498359]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76960505306266,41.890951964598784]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0004/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p4","metadata":[{"label":"streets","value":"8"},{"label":"intersections","value":"16"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0004/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0004","type":"ImageService3","width":1473,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"254.1,2071.2 243.4,0.0 1153.5,9.3 1167.4,2075.7 254.1,2071.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0004/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1164.0,1570.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7637191,41.8994254]}},{"type":"Feature","properties":{"resourceCoords":[400.0,553.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7656212,41.9012324]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0040/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p40","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0040/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0040","type":"ImageService3","width":1466,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1370.5,2090.7 97.3,2075.3 104.7,26.4 1369.7,38.4 1370.5,2090.7\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0040/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76689006708912,41.89487528633945]}},{"type":"Feature","properties":{"resourceCoords":[1466.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76332196495588,41.89494232093023]}},{"type":"Feature","properties":{"resourceCoords":[1466.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76319228511946,41.89106329783461]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7667603872527,41.890996263243835]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0041/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p41","metadata":[{"label":"streets","value":"2"},{"label":"intersections","value":"1"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0041/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0041","type":"ImageService3","width":1464,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1326.1,2126.0 131.3,2119.1 124.0,61.0 1315.3,74.9 1326.1,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0041/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76386026958477,41.89497399702266]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76028250304786,41.89503179880211]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76016976530549,41.89116342672653]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7637475318424,41.89110562494708]}},{"type":"Feature","properties":{"resourceCoords":[124.0,61.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.763554,41.8948679]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0042/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p42","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0042/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0042","type":"ImageService3","width":1466,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"213.3,21.6 1279.9,36.4 1287.3,2126.0 220.2,2126.0 213.3,21.6\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0042/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76116131172428,41.89491969155408]}},{"type":"Feature","properties":{"resourceCoords":[1466.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7576007999825,41.89498349486888]}},{"type":"Feature","properties":{"resourceCoords":[1466.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75747737113714,41.89111272298171]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76103788287892,41.89104891966691]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0043/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p43","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0043/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0043","type":"ImageService3","width":1464,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"215.4,39.6 1229.0,47.3 1239.9,2126.0 226.8,2126.0 215.4,39.6\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0043/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75857484626403,41.89497244464503]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75502607965589,41.8950310314712]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75491258730325,41.89116776043805]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75846135391139,41.89110917361188]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0044/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p44","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0044/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0044","type":"ImageService3","width":1466,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"245.2,33.9 1036.2,46.0 1012.0,2022.6 243.0,2029.0 245.2,33.9\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0044/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75618752933883,41.894984545738666]}},{"type":"Feature","properties":{"resourceCoords":[1466.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75264790707342,41.89505974437314]}},{"type":"Feature","properties":{"resourceCoords":[1466.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75250243356888,41.891211686889775]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75604205583429,41.8911364882553]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0045/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p45","metadata":[{"label":"streets","value":"9"},{"label":"intersections","value":"12"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0045/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0045","type":"ImageService3","width":1464,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1120.9,56.5 1464.0,114.0 1464.0,2084.9 -0.0,2079.0 -0.0,79.2 1120.9,56.5\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0045/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1234.0,1599.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7506056,41.8922237]}},{"type":"Feature","properties":{"resourceCoords":[220.0,606.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.753124,41.8940018]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0046/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p46","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0046/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0046","type":"ImageService3","width":1462,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"462.4,2084.9 484.6,133.4 1244.5,143.2 1245.2,2095.8 462.4,2084.9\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0046/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75128274292764,41.895108156208416]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7477419183138,41.89518107826247]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7476004626805,41.89132118907713]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75114128729433,41.89124826702308]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0047/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p47","metadata":[{"label":"streets","value":"5"},{"label":"intersections","value":"6"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0047/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0047","type":"ImageService3","width":1465,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1219.2,52.6 1249.5,2063.5 234.8,2065.6 202.7,50.1 1219.2,52.6\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0047/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[219.0,1074.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7481936,41.8931486]}},{"type":"Feature","properties":{"resourceCoords":[1242.0,1568.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7457077,41.8922816]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0048/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p48","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0048/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0048","type":"ImageService3","width":1462,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1212.5,1086.4 1209.4,2058.9 272.9,2050.1 255.9,1099.7 276.2,1071.1 1212.5,1086.4\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0048/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74648992570111,41.89511030478939]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74293697885827,41.89519110733318]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74278023652201,41.89131800294231]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74633318336485,41.89123720039852]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0049/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p49","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0049/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0049","type":"ImageService3","width":1465,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"153.7,53.7 1465.0,49.8 1465.0,1956.0 161.0,1984.6 153.7,53.7\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0049/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74390519122164,41.8951391805479]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74036122794426,41.895201313221904]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74024094856195,41.89134591413979]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74378491183933,41.89128378146579]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0005/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p5","metadata":[{"label":"streets","value":"7"},{"label":"intersections","value":"12"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0005/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0005","type":"ImageService3","width":1463,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1318.1,83.0 1342.8,2060.7 143.2,2060.5 115.7,0.0 1291.7,0.0 1303.2,39.5 1318.1,83.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0005/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1336.0,1557.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7608017,41.8994535]}},{"type":"Feature","properties":{"resourceCoords":[123.0,546.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7637852,41.9012521]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0050/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p50","metadata":[{"label":"streets","value":"5"},{"label":"intersections","value":"5"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0050/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0050","type":"ImageService3","width":1462,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1462.0,2022.5 1290.0,2022.6 1257.9,2126.0 231.8,2126.0 234.5,1971.0 -0.0,1965.7 -0.0,55.2 202.3,60.2 203.5,0.0 1462.0,0.0 1462.0,2022.5\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0050/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[235.0,1971.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7430776,41.8876008]}},{"type":"Feature","properties":{"resourceCoords":[234.0,61.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7433125,41.8914276]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0053/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p53","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0053/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0053","type":"ImageService3","width":1462,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,2126.0 -0.0,79.7 127.6,79.6 127.8,30.7 1313.4,48.1 1308.7,1669.9 1269.5,1669.5 1267.8,1836.4 120.3,1828.0 131.0,2126.0 -0.0,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0053/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77531896030747,41.89105682870079]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77180280622044,41.89113084023958]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7716592463469,41.887297599981416]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77517540043394,41.88722358844262]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0054/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p54","metadata":[{"label":"streets","value":"5"},{"label":"intersections","value":"6"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0054/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0054","type":"ImageService3","width":1464,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"130.1,1753.0 131.5,47.6 1183.9,60.0 1190.3,1822.9 130.1,1753.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0054/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1012.0,1187.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7699396,41.8890086]}},{"type":"Feature","properties":{"resourceCoords":[1012.0,58.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7700092,41.8910582]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0055/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p55","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"20"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0055/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0055","type":"ImageService3","width":1462,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1098.6,1870.8 1075.9,2126.0 -0.0,2126.0 -0.0,35.8 1254.0,55.0 1250.3,1882.1 1098.6,1870.8\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0055/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[732.0,1044.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7677315,41.8892682]}},{"type":"Feature","properties":{"resourceCoords":[1254.0,55.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7665267,41.8910932]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0056/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p56","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"9"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0056/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0056","type":"ImageService3","width":1464,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"616.4,2126.0 614.2,1894.5 87.7,1861.9 63.2,31.1 1335.0,31.5 1347.8,2126.0 616.4,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0056/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[602.0,1032.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7651807,41.8892903]}},{"type":"Feature","properties":{"resourceCoords":[1352.0,1032.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7633528,41.8893086]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0057/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p57","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0057/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0057","type":"ImageService3","width":1462,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"119.0,43.2 1314.9,48.6 1335.4,2126.0 117.7,2126.0 119.0,43.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0057/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76371952409593,41.89119814128479]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76015015830734,41.891252485860086]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76004474615685,41.88736124281398]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76361411194544,41.887306898238684]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0058/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p58","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0058/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0058","type":"ImageService3","width":1464,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1285.3,92.0 1283.6,1906.5 1286.0,1911.8 1281.4,2126.0 224.0,2112.1 223.3,85.6 1285.3,92.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0058/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76105407086129,41.891202944070955]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75748197102227,41.891282938324096]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75732701802168,41.88739403852638]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7608991178607,41.88731404427324]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0059/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p59","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0059/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0059","type":"ImageService3","width":1462,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"240.4,1928.0 220.2,90.4 1235.3,86.2 1253.8,1939.4 240.4,1928.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0059/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75844830572944,41.89127501328989]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75491120505485,41.89132250156728]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7548190919106,41.88746643959303]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7583561925852,41.88741895131564]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0006/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p6","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0006/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0006","type":"ImageService3","width":1466,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"53.1,81.3 26.9,0.0 1353.5,0.0 1354.9,2058.0 80.4,2059.4 53.1,81.3\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0006/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76102571668339,41.9022660162619]}},{"type":"Feature","properties":{"resourceCoords":[1466.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75748767605603,41.90229900226609]}},{"type":"Feature","properties":{"resourceCoords":[1466.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75742385659346,41.89845310248739]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76096189722082,41.898420116483194]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0060/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p60","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0060/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0060","type":"ImageService3","width":1464,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"236.2,1926.2 253.1,0.0 1256.8,0.0 1240.0,1946.4 236.2,1926.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0060/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.756076064415,41.8913077465649]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75252331765962,41.89140521560156]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7523345148743,41.88753738989771]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75588726162968,41.88743992086105]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0061/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p61","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0061/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0061","type":"ImageService3","width":1462,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1236.5,56.2 1242.0,1969.5 228.7,1961.6 221.7,37.4 1236.5,56.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0061/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75356093139533,41.8913876129589]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7500331362128,41.891451867338176]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7499085015649,41.88760595767108]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75343629674742,41.8875417032918]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0062/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p62","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"8"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0062/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0062","type":"ImageService3","width":1464,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1239.5,62.8 1267.3,1984.0 259.4,1976.5 232.9,63.4 1239.5,62.8\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0062/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1254.0,1066.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.74806,41.8895504]}},{"type":"Feature","properties":{"resourceCoords":[240.0,566.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7505407,41.890431]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0063/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p63","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0063/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0063","type":"ImageService3","width":1465,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1240.0,1960.5 225.5,1953.1 215.9,31.3 1231.9,40.5 1240.0,1960.5\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0063/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74864997349185,41.89141300557801]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74511541182389,41.891473469542255]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74499836961103,41.88762807480336]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74853293127899,41.88756761083911]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0064/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p64","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"7"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0064/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0064","type":"ImageService3","width":1464,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"226.0,38.5 937.1,42.6 976.4,2126.0 226.0,2126.0 226.0,38.5\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0064/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[226.0,1039.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7456102,41.8895778]}},{"type":"Feature","properties":{"resourceCoords":[226.0,1955.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7455504,41.8879181]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0065/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p65","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0065/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0065","type":"ImageService3","width":1465,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,2126.0 12.3,302.1 133.6,318.2 131.6,0.0 1332.2,0.0 1343.5,2120.1 -0.0,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0065/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7752195624758,41.887762192844455]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7717324106892,41.88781636252993]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77162755803937,41.88402234768292]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77511470982597,41.883968177997446]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0066/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p66","metadata":[{"label":"streets","value":"5"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0066/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0066","type":"ImageService3","width":1464,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"36.3,154.5 -0.0,154.6 -0.0,-0.0 36.1,0.0 36.7,88.1 1025.2,146.2 1028.5,454.1 1464.0,449.5 1464.0,508.2 1429.9,507.9 1448.5,2047.8 52.2,2098.3 36.3,154.5\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0066/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7721531,41.8881109]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7683253,41.8881625]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76822460000001,41.8840243]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7720524,41.8839727]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0067/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p67","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0067/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0067","type":"ImageService3","width":1465,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1423.0,2047.8 73.0,2042.2 66.5,1993.7 67.8,392.0 104.5,392.6 105.1,329.7 357.3,329.4 369.1,361.6 383.2,329.4 719.6,328.9 742.0,73.5 1424.0,124.5 1423.0,2047.8\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0067/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76858042546357,41.887881238995604]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76503157342599,41.88795386196317]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76489100228001,41.884092709331625]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76843985431759,41.88402008636406]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0068/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p68","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0068/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0068","type":"ImageService3","width":1465,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"785.0,355.4 758.8,407.3 1363.5,361.8 1370.7,2052.5 58.4,2059.4 46.2,350.4 785.0,355.4\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0068/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76523842903391,41.88793782965693]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7617039492427,41.887991386499486]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76160028300765,41.884145872355354]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76513476279887,41.884092315512795]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0069/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p69","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0069/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0069","type":"ImageService3","width":1465,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,1918.4 -0.0,248.4 1465.0,258.1 1465.0,294.4 1378.5,293.5 1356.0,2126.0 648.3,2082.8 650.7,1933.7 -0.0,1918.4\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0069/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76194590594251,41.88778810027799]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75836797765321,41.88785362711499]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75824114234608,41.883960828446305]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76181907063538,41.8838953016093]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0007/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p7","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0007/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0007","type":"ImageService3","width":1463,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,2056.8 -0.0,-0.0 1202.7,0.0 1202.7,39.6 1324.7,39.5 1333.4,2056.3 -0.0,2056.8\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0007/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75775937171753,41.902306450809036]}},{"type":"Feature","properties":{"resourceCoords":[1463.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7542171552386,41.90234130643404]}},{"type":"Feature","properties":{"resourceCoords":[1463.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7541495802145,41.89848297409948]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75769179669342,41.89844811847448]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0070/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p70","metadata":[{"label":"streets","value":"5"},{"label":"intersections","value":"6"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0070/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0070","type":"ImageService3","width":1465,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,253.7 87.4,253.6 87.0,216.7 326.9,220.6 327.7,0.0 1339.3,0.0 1369.3,1914.2 355.6,1934.9 358.9,2126.0 -0.0,2126.0 -0.0,253.7\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0070/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[852.0,1200.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7564742,41.8856276]}},{"type":"Feature","properties":{"resourceCoords":[1358.0,1200.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7552508,41.8856386]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0071/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p71","metadata":[{"label":"streets","value":"7"},{"label":"intersections","value":"10"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0071/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0071","type":"ImageService3","width":1459,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"180.3,2022.5 185.2,72.1 876.2,81.6 876.5,2032.2 180.3,2022.5\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0071/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[182.0,1292.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7552508,41.8856386]}},{"type":"Feature","properties":{"resourceCoords":[1200.0,86.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7528942,41.8878492]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0072/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p72","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"7"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0072/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0072","type":"ImageService3","width":1465,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1318.0,2022.0 -0.0,2003.4 -0.0,487.1 -0.0,81.6 1322.2,99.8 1342.9,265.4 1318.0,2022.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0072/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1318.0,2022.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7503165,41.8843919]}},{"type":"Feature","properties":{"resourceCoords":[319.0,86.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7528942,41.8878492]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0073/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p73","metadata":[{"label":"streets","value":"7"},{"label":"intersections","value":"13"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0073/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0073","type":"ImageService3","width":1459,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1240.3,1982.6 232.0,1971.0 252.4,214.5 231.3,49.0 996.4,66.0 995.5,661.0 1239.0,687.0 1240.3,1982.6\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0073/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[740.0,1270.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7491258,41.8856895]}},{"type":"Feature","properties":{"resourceCoords":[232.0,1971.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7503165,41.8843919]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0074/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p74","metadata":[{"label":"streets","value":"7"},{"label":"intersections","value":"19"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0074/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0074","type":"ImageService3","width":1465,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1251.3,1999.1 248.1,1989.0 244.8,686.8 -0.0,661.0 -0.0,63.0 1249.9,78.7 1251.3,1999.1\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0074/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[750.0,1994.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7466394,41.8844365]}},{"type":"Feature","properties":{"resourceCoords":[1250.0,277.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7455375,41.8875601]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0075/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p75","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0075/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0075","type":"ImageService3","width":1459,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"220.6,279.0 974.6,251.7 975.2,281.6 1236.0,282.5 1241.2,2084.7 223.6,2074.2 220.6,279.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0075/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74608900184413,41.888056564105646]}},{"type":"Feature","properties":{"resourceCoords":[1459.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74255492896619,41.88812417257279]}},{"type":"Feature","properties":{"resourceCoords":[1459.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74242352563527,41.88426329391154]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74595759851321,41.884195685444396]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0076/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p76","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0076/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0076","type":"ImageService3","width":1465,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"261.6,1985.0 235.7,454.2 1366.5,407.4 1384.0,1979.8 261.6,1985.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0076/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74365548680501,41.88811878741137]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74006896479433,41.8881495894437]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74000934335024,41.8842474601715]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74359586536092,41.884216658139174]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0077/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p77","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0077/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0077","type":"ImageService3","width":1461,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"270.3,304.1 492.6,268.4 485.8,0.0 1461.0,0.0 1461.0,270.8 1160.8,269.0 1169.3,1977.8 273.7,1973.8 270.3,304.1\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0077/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74097059036005,41.888077673741144]}},{"type":"Feature","properties":{"resourceCoords":[1461.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73744234078463,41.88813207592797]}},{"type":"Feature","properties":{"resourceCoords":[1461.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73733674976947,41.884282837801614]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7408649993449,41.88422843561479]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0078/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p78","metadata":[{"label":"streets","value":"7"},{"label":"intersections","value":"10"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0078/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0078","type":"ImageService3","width":1465,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"233.3,1955.3 235.9,268.4 1234.5,280.5 1232.2,1965.9 233.3,1955.3\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0078/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[234.0,1516.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7380759,41.885346]}},{"type":"Feature","properties":{"resourceCoords":[1234.0,280.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7356934,41.887661]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0079/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p79","metadata":[{"label":"streets","value":"7"},{"label":"intersections","value":"9"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0079/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0079","type":"ImageService3","width":1461,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,261.2 -0.0,-0.0 1012.8,0.0 983.5,1986.8 224.0,1979.7 232.4,264.9 -0.0,261.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0079/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1246.0,278.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7332324,41.887693]}},{"type":"Feature","properties":{"resourceCoords":[224.0,1976.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7355874,41.8845702]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0008/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p8","metadata":[{"label":"streets","value":"7"},{"label":"intersections","value":"12"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0008/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0008","type":"ImageService3","width":1466,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1288.4,2060.2 128.0,2060.0 120.7,49.6 -0.0,49.6 -0.0,-0.0 1466.0,0.0 1466.0,1057.7 1286.7,1057.7 1288.4,2060.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0008/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[128.0,2060.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7544655,41.8986064]}},{"type":"Feature","properties":{"resourceCoords":[1128.0,49.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.752087,41.9022926]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0080/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p80","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"14"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0080/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0080","type":"ImageService3","width":1466,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"248.3,1979.6 -0.0,1979.8 -0.0,2.2 1466.0,0.0 1466.0,270.2 1243.8,269.8 1256.8,2087.4 249.0,2083.5 248.3,1979.6\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0080/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[241.0,706.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7332053,41.8869115]}},{"type":"Feature","properties":{"resourceCoords":[1256.0,1979.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7306819,41.8846296]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0081/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p81","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"9"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0081/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0081","type":"ImageService3","width":1461,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"448.2,230.7 449.9,0.0 1002.0,0.0 1000.8,235.8 1228.6,237.8 1231.5,2016.5 226.0,2012.9 226.0,228.6 448.2,230.7\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0081/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[226.0,759.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7307474,41.8867696]}},{"type":"Feature","properties":{"resourceCoords":[226.0,1938.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7306819,41.8846296]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0082/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p82","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0082/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0082","type":"ImageService3","width":1466,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1466.0,0.0 1466.0,1899.6 239.1,1923.5 227.0,243.4 -0.0,242.5 -0.0,-0.0 1466.0,0.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0082/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.72889873005303,41.88819568966424]}},{"type":"Feature","properties":{"resourceCoords":[1466.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.72531273105942,41.88824258718814]}},{"type":"Feature","properties":{"resourceCoords":[1466.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.72522201640238,41.88434369529359]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.728808015396,41.884296797769686]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0083/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p83","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0083/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0083","type":"ImageService3","width":1461,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1325.8,2126.0 -0.0,2126.0 -0.0,-0.0 1336.3,19.3 1325.8,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0083/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77517107335662,41.88398997637465]}},{"type":"Feature","properties":{"resourceCoords":[1461.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7716149370023,41.88407047936573]}},{"type":"Feature","properties":{"resourceCoords":[1461.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77145869608232,41.88019056873019]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77501483243664,41.88011006573911]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0084/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p84","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0084/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0084","type":"ImageService3","width":1464,"height":2127},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,2127.0 -0.0,2072.8 20.2,2124.1 16.6,80.9 1464.0,37.9 1464.0,2127.0 -0.0,2127.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0084/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7719648990041,41.884183815575845]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76819504567487,41.88425027639879]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,2127.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76806626155954,41.88014369254067]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2127.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.77183611488877,41.88007723171773]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0085/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p85","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0085/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0085","type":"ImageService3","width":1460,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1392.2,20.3 1393.1,2126.0 94.8,2126.0 99.8,16.8 1392.2,20.3\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0085/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76844057983911,41.88420353867771]}},{"type":"Feature","properties":{"resourceCoords":[1460.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76483154140767,41.88427354362568]}},{"type":"Feature","properties":{"resourceCoords":[1460.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76469558174242,41.88033322840677]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76830462017385,41.8802632234588]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0086/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p86","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0086/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0086","type":"ImageService3","width":1464,"height":2127},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1410.0,4.0 1403.5,2127.0 -0.0,2127.0 56.0,2105.1 60.0,0.0 1410.0,4.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0086/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76514497369047,41.884211733250694]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76154181859883,41.88428798218231]}},{"type":"Feature","properties":{"resourceCoords":[1464.0,2127.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76139406735194,41.88036299366498]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2127.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76499722244358,41.88028674473337]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0087/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p87","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0087/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0087","type":"ImageService3","width":1465,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"20.8,0.0 602.2,0.0 599.7,147.9 1288.6,191.5 1301.5,2126.0 -0.0,2126.0 20.8,0.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0087/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76172466133178,41.88424815307301]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75811651830483,41.88431736806624]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75798255148023,41.88039147981931]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.76159069450718,41.88032226482608]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0088/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p88","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0088/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0088","type":"ImageService3","width":1466,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1351.3,2126.0 -0.0,2115.6 -0.0,171.8 12.7,179.3 365.3,186.5 365.8,0.0 1361.9,0.0 1351.3,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0088/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75855257617764,41.88427228966744]}},{"type":"Feature","properties":{"resourceCoords":[1466.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7549466086668,41.884359511304794]}},{"type":"Feature","properties":{"resourceCoords":[1466.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75477790472333,41.88043866886871]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75838387223416,41.88035144723136]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0089/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p89","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0089/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0089","type":"ImageService3","width":1465,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"202.7,2126.0 221.8,5.1 1194.8,24.7 1174.4,2126.0 202.7,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0089/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75576046988999,41.884327178201794]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75207512445311,41.88442760784777]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7518807410139,41.88041772077016]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75556608645078,41.880317291124186]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0009/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p9","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0009/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0009","type":"ImageService3","width":1475,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1369.3,0.0 1370.4,2086.0 -0.0,2083.2 -0.0,1067.8 182.9,1068.2 184.8,0.0 1369.3,0.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0009/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75170479119055,41.902379489375484]}},{"type":"Feature","properties":{"resourceCoords":[1475.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74816783358007,41.9024207477094]}},{"type":"Feature","properties":{"resourceCoords":[1475.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74808849619804,41.89859949151706]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75162545380851,41.898558233183145]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0090/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p90","metadata":[{"label":"streets","value":"5"},{"label":"intersections","value":"6"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0090/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0090","type":"ImageService3","width":1460,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"240.9,32.5 1187.9,42.2 1189.9,2124.8 241.0,2104.0 240.9,32.5\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0090/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[241.0,1416.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7526585,41.8817146]}},{"type":"Feature","properties":{"resourceCoords":[241.0,722.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7527056,41.8830429]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0091/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p91","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0091/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0091","type":"ImageService3","width":1465,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"235.3,15.5 1465.0,33.8 1465.0,733.2 1207.7,729.2 1200.2,2106.1 803.6,2126.0 503.7,2126.0 227.9,2126.0 227.9,2126.0 235.3,15.5\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0091/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75091052091027,41.88440739537939]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74722063017522,41.88449336922687]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74705422605193,41.88047854019216]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.75074411678698,41.88039256634468]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0092/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p92","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0092/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0092","type":"ImageService3","width":1460,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"281.8,2096.0 270.2,725.8 307.5,725.8 509.9,726.1 526.4,726.1 516.7,30.1 1225.1,30.9 1249.4,2096.8 281.8,2096.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0092/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74852729589414,41.88446981062425]}},{"type":"Feature","properties":{"resourceCoords":[1460.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74483127437111,41.884517363437226]}},{"type":"Feature","properties":{"resourceCoords":[1460.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74473891968488,41.88048209364981]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7484349412079,41.88043454083684]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0093/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p93","metadata":[{"label":"streets","value":"4"},{"label":"intersections","value":"8"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0093/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0093","type":"ImageService3","width":1465,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"242.5,2126.0 213.6,0.0 1230.9,0.0 1257.2,2126.0 242.5,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0093/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[230.0,1380.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7453282,41.8818115]}},{"type":"Feature","properties":{"resourceCoords":[1248.0,1380.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.742861,41.8818396]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0094/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p94","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0094/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0094","type":"ImageService3","width":1460,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1460.0,2105.7 255.8,2126.0 265.6,11.1 1460.0,30.6 1460.0,2105.7\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0094/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74364320006435,41.8844856730364]}},{"type":"Feature","properties":{"resourceCoords":[1460.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73988985315658,41.88457715978159]}},{"type":"Feature","properties":{"resourceCoords":[1460.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73971217203226,41.88047930655983]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74346551894003,41.880387819814636]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0095/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p95","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0095/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0095","type":"ImageService3","width":1465,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1146.8,0.9 1133.3,2118.2 418.7,2107.1 417.2,0.1 1146.8,0.9\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0095/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74093760928345,41.88447328568468]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73724687683811,41.88456132571281]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73707647326151,41.88054558835816]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.74076720570685,41.88045754833003]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0096/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p96","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0096/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0096","type":"ImageService3","width":1465,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1213.2,2122.2 249.7,2115.9 244.5,14.2 1213.9,20.8 1213.2,2122.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0096/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73866998617314,41.88455672275928]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73495112075778,41.88462077058336]}},{"type":"Feature","properties":{"resourceCoords":[1465.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73482715456986,41.88057442598256]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73854601998521,41.880510378158476]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0097/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p97","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0097/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0097","type":"ImageService3","width":1462,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1184.7,2122.3 217.6,2105.9 240.0,0.0 1208.1,13.1 1184.7,2122.3\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0097/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73619400938702,41.884548379925924]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7324980544445,41.88464063295415]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.73231912992459,41.88061096544651]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7360150848671,41.88051871241828]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0098/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p98","metadata":[{"label":"streets","value":"4"},{"label":"intersections","value":"4"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0098/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0098","type":"ImageService3","width":1465,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"215.9,0.0 1020.7,0.0 1034.2,2125.2 237.7,2126.0 215.9,0.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0098/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[230.0,1374.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7330606,41.8819521]}},{"type":"Feature","properties":{"resourceCoords":[1251.0,1374.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7306058,41.8819736]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0099/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1950 | sanborn01790_105 p99","metadata":[{"label":"streets","value":"4"},{"label":"intersections","value":"0"}],"created":"2026-09-21T04:37:26Z","modified":"2026-09-21T04:37:26Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0099/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0099","type":"ImageService3","width":1462,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1217.5,2110.7 -0.0,2107.9 -0.0,33.5 212.1,34.9 212.1,0.0 1207.5,0.0 1217.5,2110.7\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195018:01790_18_1950-0099/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7311999,41.8844896]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7276004,41.8845381]}},{"type":"Feature","properties":{"resourceCoords":[1462.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7275056,41.880641]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7311051,41.8805925]}}]}}]}