{"id":"https://data.mapsnap.org/runs/v1.3/iiif/chronoscope/sanborn01790_066.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":"81"},{"label":"placed","value":"78"},{"label":"unplaced","value":"3"},{"label":"fit sources","value":"georef 46, georef-snap 32"},{"label":"key map","value":"georeferenced"},{"label":"split sheets","value":"1 sheet(s) cut into 2 panels"},{"label":"unplaced pages","value":"p0 (tier 4, 41.70189,-87.69189 +/-3330m); p66 (tier 1, 41.69274,-87.70322 +/-525m); p79 (tier 1, 41.70271,-87.68666 +/-526m)"}],"items":[{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p1","metadata":[{"label":"streets","value":"8"},{"label":"intersections","value":"28"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0001/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0001","type":"ImageService3","width":1420,"height":2127},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"210.9,1812.3 -0.0,1673.8 -0.0,1190.2 211.0,218.7 317.6,0.0 851.8,0.0 1413.5,0.0 1420.0,556.8 1420.0,882.3 1420.0,1227.3 1420.0,1862.5 1420.0,2127.0 941.1,2127.0 210.9,1812.3\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0001/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[211.0,704.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.681327,41.6972798]}},{"type":"Feature","properties":{"resourceCoords":[211.0,562.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6813435,41.697811]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p10","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"12"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0010/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0010","type":"ImageService3","width":1421,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1236.8,988.2 1238.8,1988.8 459.7,1993.0 129.0,987.4 101.4,986.7 117.8,86.1 305.9,104.1 233.4,56.2 221.4,0.0 702.9,0.0 702.9,0.0 1114.5,0.0 1116.2,988.0 1236.8,988.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0010/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[670.0,987.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6685188,41.6913124]}},{"type":"Feature","properties":{"resourceCoords":[670.0,1993.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6694934,41.6896154]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0011/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_066 p11","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0011/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0011","type":"ImageService3","width":1421,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"749.9,1660.9 -0.0,1871.1 -0.0,913.8 64.0,-0.0 98.8,-0.0 158.1,-0.0 943.8,673.3 1421.0,1134.5 1421.0,1162.4 1421.0,1226.5 749.9,1660.9\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0011/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.66948280913198,41.69413756608576]}},{"type":"Feature","properties":{"resourceCoords":[1421.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.66932003639634,41.6889357012655]}},{"type":"Feature","properties":{"resourceCoords":[1421.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.67966923563621,41.68875256584871]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.67983200837185,41.69395443066897]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p12","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0012/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0012","type":"ImageService3","width":1421,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1269.8,1783.7 1421.0,1782.3 1421.0,2126.0 724.1,2126.0 725.3,1788.5 -0.0,1794.9 -0.0,303.6 626.4,294.9 623.9,-0.0 721.9,-0.0 723.7,293.7 1260.0,282.2 1269.8,1783.7\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.67680185507955,41.693181504004954]}},{"type":"Feature","properties":{"resourceCoords":[1421.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.67675154965889,41.690564037090766]}},{"type":"Feature","properties":{"resourceCoords":[1421.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.68195907438206,41.690507438839916]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.68200937980272,41.693124905754104]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p13","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"14"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0013/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0013","type":"ImageService3","width":1421,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,1375.0 -0.0,876.4 254.2,850.5 208.0,146.2 962.3,108.7 952.3,0.0 1421.0,0.0 1421.0,1493.6 280.2,1542.3 270.9,1362.5 -0.0,1375.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0013/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[605.0,1874.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6794332,41.6844714]}},{"type":"Feature","properties":{"resourceCoords":[722.0,1122.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6787588,41.6871936]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p14","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0014/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0014","type":"ImageService3","width":1421,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"591.1,1764.5 499.9,1695.4 432.6,1605.9 456.1,1572.9 494.1,701.7 586.1,700.9 611.0,600.6 666.6,495.9 768.9,400.8 928.8,318.4 1042.8,220.0 1126.4,97.0 1126.8,1855.6 860.6,1854.7 591.1,1764.5\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.67774899398624,41.69137418557972]}},{"type":"Feature","properties":{"resourceCoords":[1421.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.67082562882969,41.69145147091614]}},{"type":"Feature","properties":{"resourceCoords":[1421.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.6706718775638,41.68366153286143]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.67759524272036,41.683584247525005]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p15","metadata":[{"label":"streets","value":"8"},{"label":"intersections","value":"13"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0015/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0015","type":"ImageService3","width":1421,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,1805.7 -0.0,46.2 20.6,0.0 37.1,0.0 1.8,295.1 452.2,482.2 460.5,411.5 1341.8,803.5 899.8,1800.3 -0.0,1805.7\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0015/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[364.0,1806.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6703415,41.684655]}},{"type":"Feature","properties":{"resourceCoords":[818.0,569.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6682038,41.6892113]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p16","metadata":[{"label":"streets","value":"12"},{"label":"intersections","value":"20"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0016/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0016","type":"ImageService3","width":1421,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1345.6,583.9 1421.0,401.8 1421.0,2126.0 354.2,2126.0 349.8,1808.6 37.1,1811.5 480.7,815.7 786.0,952.6 957.2,572.0 1218.1,680.0 1247.2,583.4 1345.6,583.9\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0016/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[633.0,1806.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6647878,41.684762]}},{"type":"Feature","properties":{"resourceCoords":[379.0,1044.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6660974,41.6875383]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p17","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0017/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0017","type":"ImageService3","width":1421,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,1955.0 -0.0,818.0 36.5,819.6 69.4,843.0 197.5,731.9 253.4,622.6 316.9,416.4 322.3,196.6 1421.0,313.2 1421.0,1957.5 1302.3,1959.9 1302.9,2126.0 570.4,2126.0 570.4,2126.0 366.5,2126.0 322.5,1960.8 -0.0,1955.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.67140701573943,41.68581238168232]}},{"type":"Feature","properties":{"resourceCoords":[1421.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.67130908651671,41.680585564503055]}},{"type":"Feature","properties":{"resourceCoords":[1421.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.68170657509853,41.68047537010174]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.68180450432125,41.685702187281]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p18","metadata":[{"label":"streets","value":"10"},{"label":"intersections","value":"41"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0018/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0018","type":"ImageService3","width":1421,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"444.4,304.6 1320.5,411.3 1322.3,142.6 1379.8,160.1 1379.9,-0.0 1421.0,-0.0 1421.0,2126.0 -0.0,2126.0 -0.0,2094.4 293.5,2099.8 295.9,1935.1 414.6,1934.9 444.4,304.6\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0018/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[509.0,695.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6747535,41.6802863]}},{"type":"Feature","properties":{"resourceCoords":[1312.0,1561.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6788952,41.677227]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p19","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0019/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0019","type":"ImageService3","width":1421,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"167.7,2067.5 -0.0,2066.6 -0.0,1173.5 137.8,58.6 1180.3,64.6 1160.9,2126.0 149.6,2126.0 167.7,2067.5\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.67301706156202,41.68481319306264]}},{"type":"Feature","properties":{"resourceCoords":[1421.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.6661879817433,41.68497349027523]}},{"type":"Feature","properties":{"resourceCoords":[1421.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.66586911946665,41.677288852855895]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.67269819928536,41.6771285556433]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p2","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0002/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0002","type":"ImageService3","width":1420,"height":2127},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"51.1,1899.5 48.9,1788.9 152.3,1751.7 261.5,1618.2 313.2,1479.7 340.3,1331.5 329.6,1080.5 284.9,900.8 538.9,900.9 537.8,570.0 43.0,575.6 39.6,242.8 529.6,240.9 529.2,4.0 1420.0,0.0 1420.0,1884.2 1235.7,2127.0 543.1,2127.0 542.4,1897.4 51.1,1899.5\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.67797174312975,41.69999360047224]}},{"type":"Feature","properties":{"resourceCoords":[1420.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.67102234897817,41.70009757530487]}},{"type":"Feature","properties":{"resourceCoords":[1420.0,2127.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.67081523129183,41.6922701978085]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2127.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.6777646254434,41.692166222975864]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p20","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0020/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0020","type":"ImageService3","width":1421,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"244.4,372.2 1336.4,377.7 1338.2,0.0 1421.0,0.0 1421.0,2126.0 183.4,2126.0 183.3,2116.1 -0.0,2117.8 -0.0,50.7 241.3,49.8 244.4,372.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0020/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.66734012127091,41.68489554735036]}},{"type":"Feature","properties":{"resourceCoords":[1421.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.66052802517204,41.68500699350024]}},{"type":"Feature","properties":{"resourceCoords":[1421.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.66030633695884,41.677341473924706]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.66711843305771,41.677230027774826]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p21","metadata":[{"label":"streets","value":"5"},{"label":"intersections","value":"5"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0021/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0021","type":"ImageService3","width":1421,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,1924.5 -0.0,998.5 167.0,976.6 198.2,0.0 1421.0,0.0 1421.0,1927.8 -0.0,1924.5\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0021/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1200.0,1042.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6820165,41.719107]}},{"type":"Feature","properties":{"resourceCoords":[1200.0,2026.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6819521,41.7172922]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p22","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"9"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0022/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0022","type":"ImageService3","width":1421,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,-0.0 1420.2,0.0 1421.0,2053.8 -0.0,2031.8 -0.0,-0.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0022/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1201.0,1074.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6818934,41.7154788]}},{"type":"Feature","properties":{"resourceCoords":[1201.0,98.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6819521,41.7172922]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p23","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"11"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0023/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0023","type":"ImageService3","width":1421,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"197.5,1019.5 201.2,2029.5 -0.0,2028.5 -0.0,58.9 1421.0,76.6 1421.0,2044.1 684.0,2028.0 683.8,1954.5 497.3,1953.2 493.9,1022.0 197.5,1019.5\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0023/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1202.0,74.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6818352,41.7136643]}},{"type":"Feature","properties":{"resourceCoords":[684.0,2028.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6830172,41.7100282]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p24","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0024/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0024","type":"ImageService3","width":1421,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"693.9,2029.5 509.3,2027.3 487.6,0.0 674.3,0.0 675.0,73.1 1413.0,84.2 1420.7,2038.0 1215.0,2037.6 1216.0,2126.0 694.8,2126.0 693.9,2029.5\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0024/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.68469128488056,41.71014641446262]}},{"type":"Feature","properties":{"resourceCoords":[1421.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.68117254419217,41.71018408690372]}},{"type":"Feature","properties":{"resourceCoords":[1421.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.68109757473226,41.706226185165264]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.68461631542066,41.70618851272416]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p25","metadata":[{"label":"streets","value":"5"},{"label":"intersections","value":"6"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0025/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0025","type":"ImageService3","width":1421,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1421.0,2064.8 -0.0,2037.8 -0.0,66.1 699.0,81.0 699.0,177.6 1216.9,182.4 1216.7,93.9 1421.0,96.2 1421.0,2064.8\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0025/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[699.0,81.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6829015,41.7063865]}},{"type":"Feature","properties":{"resourceCoords":[699.0,2044.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6827856,41.7027358]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p26","metadata":[{"label":"streets","value":"5"},{"label":"intersections","value":"6"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0026/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0026","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,69.9 1117.5,79.8 1274.9,95.2 1416.0,96.8 1416.0,2057.8 1.0,2031.5 -0.0,69.9\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0026/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[686.0,76.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6827856,41.7027358]}},{"type":"Feature","properties":{"resourceCoords":[686.0,2038.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6826696,41.6990818]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p27","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"8"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0027/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0027","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"221.2,2126.0 -0.0,2126.0 -0.0,80.5 1208.1,79.2 1238.2,1016.9 1228.1,2061.7 1157.2,2046.1 801.4,2047.0 802.2,2126.0 711.2,2126.0 710.4,2047.2 220.3,2048.3 221.2,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0027/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1218.0,1060.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.681327,41.6972798]}},{"type":"Feature","properties":{"resourceCoords":[207.0,1060.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6838337,41.6972554]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p28","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"18"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0028/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0028","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,2047.3 -0.0,150.6 189.1,152.6 189.0,75.0 679.0,79.0 679.0,157.8 770.0,158.8 769.5,1056.8 1196.0,1060.6 1195.5,2058.6 -0.0,2047.3\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0028/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[679.0,1056.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6824964,41.6936313]}},{"type":"Feature","properties":{"resourceCoords":[679.0,79.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6825538,41.69544]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p29","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0029/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0029","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1196.9,84.9 1191.7,1057.8 1022.9,1057.0 1018.4,1953.6 412.1,1948.7 412.3,1896.1 170.8,1895.1 170.3,2023.6 -0.0,2022.0 -0.0,-0.0 1028.2,5.1 1027.8,84.3 1196.9,84.9\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.69817576423598,41.73551362325718]}},{"type":"Feature","properties":{"resourceCoords":[1416.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.69126631869992,41.73564205638784]}},{"type":"Feature","properties":{"resourceCoords":[1416.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.69100973621717,41.72784567138671]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.69791918175324,41.72771723825605]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p3","metadata":[{"label":"streets","value":"8"},{"label":"intersections","value":"12"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0003/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0003","type":"ImageService3","width":1420,"height":2127},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1170.1,1154.2 1275.2,1319.3 993.1,1819.9 775.0,1717.5 770.6,1736.2 769.7,1717.1 596.6,1641.3 597.6,1547.5 313.4,1739.5 338.1,0.0 1173.2,0.0 1170.1,1154.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0003/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1172.0,430.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6668416,41.6980712]}},{"type":"Feature","properties":{"resourceCoords":[1170.0,1154.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6667302,41.6954161]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p30","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0030/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0030","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"169.8,79.3 -0.0,79.6 -0.0,0.0 1416.0,0.0 1416.0,2126.0 165.6,2126.0 78.7,2037.5 -0.0,2037.0 -0.0,1056.6 169.6,1056.7 169.8,79.3\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0030/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.69315785015391,41.73558835650279]}},{"type":"Feature","properties":{"resourceCoords":[1416.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.68627827173032,41.73568997819179]}},{"type":"Feature","properties":{"resourceCoords":[1416.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.6860752525458,41.72792730738614]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.6929548309694,41.727825685697134]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p31","metadata":[{"label":"streets","value":"9"},{"label":"intersections","value":"19"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0031/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0031","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1033.5,0.0 1031.8,809.3 1221.1,810.4 1223.2,1807.3 229.1,1804.8 228.7,2126.0 -0.0,2126.0 -0.0,-0.0 1033.5,0.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0031/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[974.0,809.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7080947,41.726151]}},{"type":"Feature","properties":{"resourceCoords":[726.0,1806.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7092131,41.7224745]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p32","metadata":[{"label":"streets","value":"9"},{"label":"intersections","value":"19"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0032/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0032","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"189.2,813.0 -0.0,812.3 -0.0,3.3 1416.0,0.0 1416.0,1812.5 1190.6,1811.6 1192.1,1613.5 1171.3,1613.5 1168.8,1811.5 193.4,1809.5 189.2,813.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0032/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[688.0,1810.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.704337,41.7225391]}},{"type":"Feature","properties":{"resourceCoords":[933.0,318.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7032674,41.7280316]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p33","metadata":[{"label":"streets","value":"9"},{"label":"intersections","value":"20"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0033/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0033","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,1114.2 -0.0,122.8 408.6,0.0 408.6,0.0 1416.0,0.0 1416.0,1620.2 928.2,2126.0 173.3,2126.0 -0.0,1114.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0033/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[674.0,1120.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6994789,41.7244176]}},{"type":"Feature","properties":{"resourceCoords":[1177.0,128.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6971006,41.7281082]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p34","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0034/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0034","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"6.9,2076.4 -0.0,76.0 487.4,0.0 1089.8,0.0 1254.1,166.4 1416.0,165.9 1416.0,2071.4 6.9,2076.4\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.69832335184618,41.72837493710048]}},{"type":"Feature","properties":{"resourceCoords":[1416.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.69136876864376,41.728461776723506]}},{"type":"Feature","properties":{"resourceCoords":[1416.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.69119530063662,41.72061358396376]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.69814988383905,41.72052674434074]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p35","metadata":[{"label":"streets","value":"5"},{"label":"intersections","value":"15"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0035/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0035","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"57.0,396.0 1416.0,396.0 1416.0,2126.0 -0.0,2126.0 -0.0,1031.1 57.0,396.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0035/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[553.0,396.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7104221,41.7224582]}},{"type":"Feature","properties":{"resourceCoords":[57.0,396.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7116557,41.7224416]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p36","metadata":[{"label":"streets","value":"5"},{"label":"intersections","value":"9"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0036/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0036","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"211.7,1363.7 216.2,399.1 1317.8,404.2 1416.0,1437.5 1416.0,2126.0 208.0,2126.0 211.7,1363.7\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0036/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[826.0,1401.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7067129,41.7206653]}},{"type":"Feature","properties":{"resourceCoords":[826.0,402.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7067691,41.7225073]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p37","metadata":[{"label":"streets","value":"5"},{"label":"intersections","value":"6"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0037/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0037","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1181.3,404.5 1198.0,2126.0 306.3,2123.1 302.8,1525.9 198.0,1367.6 198.0,404.0 1181.3,404.5\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0037/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[690.0,404.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.704337,41.7225391]}},{"type":"Feature","properties":{"resourceCoords":[198.0,404.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.705554,41.7225238]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p38","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0038/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0038","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"180.5,393.0 659.8,0.0 701.7,0.0 1141.0,401.6 1416.0,1433.2 1416.0,1441.5 1202.7,2126.0 186.2,2126.0 180.5,393.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.70358347376033,41.723264478839226]}},{"type":"Feature","properties":{"resourceCoords":[1416.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.70013763567712,41.723325244922385]}},{"type":"Feature","properties":{"resourceCoords":[1416.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7000162571953,41.71943645553671]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.70346209527851,41.71937568945355]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p39","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0039/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0039","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,1350.5 -0.0,1283.4 -0.0,413.4 1200.5,417.1 1416.0,1421.8 1416.0,1421.8 1416.0,2126.0 1055.6,2126.0 -0.0,1350.5\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.70080209127221,41.72335755963779]}},{"type":"Feature","properties":{"resourceCoords":[1416.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.69725364512792,41.72340440115944]}},{"type":"Feature","properties":{"resourceCoords":[1416.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.69716008057003,41.719399813019756]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.70070852671432,41.719352971498104]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p4","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0004/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0004","type":"ImageService3","width":1420,"height":2127},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"164.3,1840.2 -0.0,1699.3 -0.0,1511.8 -0.0,-0.0 1314.5,0.0 1420.0,1102.3 1420.0,1353.5 1317.2,1541.1 352.9,1925.6 164.3,1840.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0004/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.66849429378269,41.69969251253035]}},{"type":"Feature","properties":{"resourceCoords":[1420.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.66156481691786,41.6998111013241]}},{"type":"Feature","properties":{"resourceCoords":[1420.0,2127.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.66132858912704,41.69200612835541]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2127.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.66825806599186,41.691887539561655]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p40","metadata":[{"label":"streets","value":"5"},{"label":"intersections","value":"6"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0040/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0040","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,1352.9 -0.0,406.5 1303.9,0.0 1416.0,0.0 1416.0,2126.0 147.4,2126.0 -0.0,1352.9\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0040/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[330.0,404.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6969483,41.7226208]}},{"type":"Feature","properties":{"resourceCoords":[1324.0,1400.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6944394,41.7207706]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p41","metadata":[{"label":"streets","value":"8"},{"label":"intersections","value":"16"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0041/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0041","type":"ImageService3","width":1419,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,2126.0 0.0,0.0 1185.9,0.0 1185.6,49.9 1419.0,52.1 1419.0,567.1 1183.8,565.2 1182.0,1063.0 1419.0,1065.0 1419.0,2126.0 -0.0,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0041/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1182.0,1063.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7163836,41.7168959]}},{"type":"Feature","properties":{"resourceCoords":[686.0,1560.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7187409,41.715031]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p42","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0042/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0042","type":"ImageService3","width":1419,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"183.0,1067.8 0.0,-0.0 1147.3,0.0 1419.0,443.9 1419.0,2126.0 999.5,2109.6 999.6,2126.0 435.7,2124.0 434.1,2014.2 183.0,1067.8\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.71734999019894,41.72079744517331]}},{"type":"Feature","properties":{"resourceCoords":[1419.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.71043557208161,41.72087200744899]}},{"type":"Feature","properties":{"resourceCoords":[1419.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.71028696122721,41.71308472385773]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.71720137934454,41.713010161582055]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p43","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0043/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0043","type":"ImageService3","width":1419,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,1987.2 -0.0,5.0 1203.3,4.5 1419.0,1213.2 1419.0,2126.0 27.9,2126.0 27.6,2003.9 -0.0,1987.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.71264739260045,41.72066549238452]}},{"type":"Feature","properties":{"resourceCoords":[1419.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.70565198468992,41.72075921451848]}},{"type":"Feature","properties":{"resourceCoords":[1419.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.70546518660647,41.712880696625]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.712460594517,41.71278697449104]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p44","metadata":[{"label":"streets","value":"9"},{"label":"intersections","value":"25"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0044/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0044","type":"ImageService3","width":1419,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"303.5,1117.9 187.1,1301.2 189.8,1988.1 -0.0,1988.1 -0.0,1192.4 80.7,1113.2 -0.0,1052.2 -0.0,944.2 109.7,856.2 185.5,711.8 184.9,377.8 926.8,380.5 927.0,509.0 1172.3,509.5 1173.7,758.1 1419.0,757.7 1419.0,1990.8 1180.4,1988.3 1181.2,2126.0 417.3,2126.0 417.4,1910.0 393.4,1910.0 395.7,1213.8 303.5,1117.9\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0044/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[927.0,509.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7029945,41.718902]}},{"type":"Feature","properties":{"resourceCoords":[1175.0,1002.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7017188,41.717104]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p45","metadata":[{"label":"streets","value":"7"},{"label":"intersections","value":"12"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0045/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0045","type":"ImageService3","width":1419,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,2051.6 -0.0,428.5 502.6,91.2 999.5,94.5 1419.0,472.5 1419.0,539.4 1419.0,585.6 1419.0,2078.1 1022.2,2126.0 223.2,2126.0 -0.0,2051.6\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0045/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1244.0,582.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6968391,41.7189811]}},{"type":"Feature","properties":{"resourceCoords":[228.0,1557.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7016542,41.7152838]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p46","metadata":[{"label":"streets","value":"10"},{"label":"intersections","value":"27"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0046/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0046","type":"ImageService3","width":1419,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"679.9,2058.9 370.8,2056.3 356.7,1061.3 302.2,1060.8 175.8,1059.5 175.3,569.0 299.0,569.8 349.7,570.1 348.1,457.4 714.3,462.4 719.3,92.3 1177.8,92.0 1183.0,2126.0 680.1,2126.0 679.9,2058.9\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0046/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1179.0,576.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6918959,41.7190312]}},{"type":"Feature","properties":{"resourceCoords":[679.0,1805.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6942335,41.7144757]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p47","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0047/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0047","type":"ImageService3","width":1419,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"434.8,2058.3 195.7,2056.0 187.9,77.7 342.3,79.3 342.5,0.0 1419.0,0.0 1419.0,57.9 1064.3,55.1 1063.9,87.0 1419.0,91.2 1419.0,2063.6 954.9,2060.0 955.2,2126.0 434.9,2121.4 434.8,2058.3\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0047/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.69287281076157,41.721081053447364]}},{"type":"Feature","properties":{"resourceCoords":[1419.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.68596771534355,41.72118143413182]}},{"type":"Feature","properties":{"resourceCoords":[1419.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.68576764462031,41.71340468616622]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.69267274003833,41.71330430548176]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0048__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_066 p48 [1]","metadata":[{"label":"streets","value":"7"},{"label":"intersections","value":"15"},{"label":"split_canvas_x","value":"0.0"},{"label":"split_canvas_y","value":"0.0"},{"label":"split_canvas_w","value":"2754.0"},{"label":"split_canvas_h","value":"8504.0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0048__1/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0048","type":"ImageService3","width":1419,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,75.8 350.8,76.0 372.4,2039.4 429.6,2039.1 430.3,2126.0 568.0,2126.0 544.7,545.5 628.3,533.0 635.0,42.4 688.5,41.5 688.5,0.0 349.9,0.0 350.4,42.8 -0.0,44.1 -0.0,75.8\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0048__1/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[332.8,1050.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6860086,41.7172683]}},{"type":"Feature","properties":{"resourceCoords":[390.7,76.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6857623,41.7208491]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0048__2/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_066 p48 [2]","metadata":[{"label":"streets","value":"7"},{"label":"intersections","value":"22"},{"label":"split_canvas_x","value":"2752.8"},{"label":"split_canvas_y","value":"0.0"},{"label":"split_canvas_w","value":"2923.2"},{"label":"split_canvas_h","value":"8504.0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0048__2/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0048","type":"ImageService3","width":1419,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1172.3,165.6 1034.9,163.3 1020.0,2047.0 992.8,2046.6 991.9,2126.0 1158.5,2126.0 1158.6,2050.2 1419.0,2056.0 1419.0,562.7 1270.1,560.9 1270.1,1068.5 1169.0,1067.7 1172.3,165.6\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0048__2/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[953.1,76.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6858986,41.7136313]}},{"type":"Feature","properties":{"resourceCoords":[1020.1,1806.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.685357,41.7072694]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p49","metadata":[{"label":"streets","value":"7"},{"label":"intersections","value":"12"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0049/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0049","type":"ImageService3","width":1419,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,218.5 1394.3,222.4 1395.0,0.0 1419.0,0.0 1419.0,2058.5 1027.0,2056.2 1027.2,1989.0 207.6,1996.7 207.8,2051.5 -0.0,2052.9 -0.0,218.5\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0049/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[945.0,1072.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7075883,41.7097279]}},{"type":"Feature","properties":{"resourceCoords":[200.0,78.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7113537,41.7133198]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p5","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"9"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0005/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0005","type":"ImageService3","width":1420,"height":2127},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"461.2,2026.1 456.8,1229.8 482.6,1084.2 469.2,958.8 274.3,303.6 -0.0,458.5 -0.0,-0.0 1420.0,0.0 1420.0,2055.2 1302.1,2122.1 1248.7,2030.3 461.2,2026.1\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0005/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[615.0,237.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6604454,41.6994262]}},{"type":"Feature","properties":{"resourceCoords":[749.0,2035.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6640398,41.693362]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p50","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0050/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0050","type":"ImageService3","width":1414,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1169.7,123.1 1414.0,118.8 1414.0,2050.9 1187.9,2051.0 1187.4,1999.4 967.6,1999.9 967.9,2126.0 939.6,2126.0 939.1,2050.2 398.2,2048.9 391.2,191.8 1170.3,188.9 1169.7,123.1\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0050/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.70725436672294,41.71357618639171]}},{"type":"Feature","properties":{"resourceCoords":[1414.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.70040796258142,41.71366433494099]}},{"type":"Feature","properties":{"resourceCoords":[1414.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7002316712041,41.70592552231323]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7070780753456,41.705837373763956]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0051/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_066 p51","metadata":[{"label":"streets","value":"7"},{"label":"intersections","value":"34"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0051/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0051","type":"ImageService3","width":1414,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"380.4,2036.2 -0.0,2035.0 -0.0,56.5 705.0,63.9 705.0,131.1 1074.1,132.4 1077.3,2042.4 1037.6,2042.1 1036.7,2126.0 379.9,2126.0 380.4,2036.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0051/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[705.0,806.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6941144,41.7108193]}},{"type":"Feature","properties":{"resourceCoords":[705.0,1302.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.694055,41.7089994]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0052/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_066 p52","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"9"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0052/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0052","type":"ImageService3","width":1414,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,2044.5 -0.0,119.5 135.6,120.2 135.7,54.2 374.3,58.1 374.0,121.5 893.0,129.5 893.2,63.2 1414.0,70.4 1395.6,2062.8 888.9,2054.1 889.0,2007.0 339.4,2000.2 339.4,2048.2 -0.0,2044.5\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0052/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[386.0,1557.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6903156,41.7081274]}},{"type":"Feature","properties":{"resourceCoords":[135.0,2046.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6914774,41.7063235]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p53","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0053/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0053","type":"ImageService3","width":1414,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,0.0 1414.0,0.0 1414.0,2068.7 955.4,2066.3 955.5,2126.0 702.5,2126.0 702.2,2065.1 -0.0,2062.1 -0.0,0.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.72184303402403,41.70610320080596]}},{"type":"Feature","properties":{"resourceCoords":[1414.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.71496154679045,41.706236127757656]}},{"type":"Feature","properties":{"resourceCoords":[1414.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.71469573248598,41.698456752751454]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.72157721971956,41.69832382579976]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p54","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0054/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0054","type":"ImageService3","width":1414,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1178.0,2065.2 1178.1,1057.8 979.9,1060.3 983.5,2064.1 925.0,2063.8 926.1,1986.8 384.5,1981.8 385.7,47.5 1414.0,51.2 1414.0,2066.6 1178.0,2065.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0054/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.71682949931332,41.70614102739141]}},{"type":"Feature","properties":{"resourceCoords":[1414.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.70997452995051,41.70627660943217]}},{"type":"Feature","properties":{"resourceCoords":[1414.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.70970340607174,41.69852721766332]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.71655837543454,41.698391635622556]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p55","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0055/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0055","type":"ImageService3","width":1414,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,2059.6 -0.0,1172.2 -0.0,1061.8 200.9,0.0 466.7,0.0 1028.2,0.0 1199.4,70.0 1196.6,1068.3 1195.8,1320.3 1187.5,2070.7 688.9,2126.0 637.8,2126.0 439.6,2126.0 -0.0,2059.6\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0055/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.71209948592556,41.70625559845307]}},{"type":"Feature","properties":{"resourceCoords":[1414.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7052109297774,41.70641070716966]}},{"type":"Feature","properties":{"resourceCoords":[1414.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.70490075784413,41.698623358654686]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7117893139923,41.698468249938095]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p56","metadata":[{"label":"streets","value":"10"},{"label":"intersections","value":"39"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0056/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0056","type":"ImageService3","width":1414,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1414.0,2055.2 179.2,2051.7 183.1,1305.0 -0.0,1304.0 -0.0,1052.8 182.3,1054.2 179.3,60.8 931.0,67.6 931.0,142.6 958.8,142.8 949.7,1060.2 1175.9,1061.9 1175.1,70.1 1412.3,71.5 1414.0,2055.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0056/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[931.0,1060.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7024205,41.7025183]}},{"type":"Feature","properties":{"resourceCoords":[931.0,2054.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7023035,41.6988587]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p57","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0057/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0057","type":"ImageService3","width":1414,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,1055.6 -0.0,-0.0 220.1,0.0 220.2,25.6 447.0,0.0 1026.9,0.0 1414.0,49.3 1414.0,1942.4 1190.0,2063.2 476.3,2061.5 -0.0,1055.6\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.70240326185166,41.706356726425476]}},{"type":"Feature","properties":{"resourceCoords":[1414.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.6955674198409,41.70645558382377]}},{"type":"Feature","properties":{"resourceCoords":[1414.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.69536973368939,41.698727841220716]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.70220557570015,41.698628983822424]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p58","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0058/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0058","type":"ImageService3","width":1414,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"206.8,2126.0 -0.0,2126.0 -0.0,48.5 429.8,47.8 429.2,0.0 932.3,0.0 932.8,47.0 1414.0,49.0 1414.0,2055.5 1241.7,2055.6 1242.5,2126.0 960.0,2126.0 958.9,2055.8 206.3,2056.2 206.8,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.69233444433088,41.70649085676123]}},{"type":"Feature","properties":{"resourceCoords":[1414.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.68546567460741,41.70656111808]}},{"type":"Feature","properties":{"resourceCoords":[1414.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.68532517217167,41.69879616023863]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.69219394189514,41.698725898919854]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p59","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0059/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0059","type":"ImageService3","width":1414,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,55.7 700.8,64.6 700.6,125.2 952.4,127.4 952.8,68.0 1414.0,74.2 1414.0,570.3 1414.0,570.4 1414.0,2126.0 -0.0,2126.0 -0.0,55.7\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.72160344382607,41.69876225727506]}},{"type":"Feature","properties":{"resourceCoords":[1414.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.71469225990883,41.69893977452457]}},{"type":"Feature","properties":{"resourceCoords":[1414.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.71433731874116,41.69112593768763]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7212485026584,41.69094842043812]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p6","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"7"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0006/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0006","type":"ImageService3","width":1420,"height":2127},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1172.0,321.1 1177.6,2127.0 176.8,2127.0 177.0,324.0 1172.0,321.1\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0006/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1175.0,1459.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6646511,41.6900766]}},{"type":"Feature","properties":{"resourceCoords":[177.0,324.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6682038,41.6892113]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p60","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0060/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0060","type":"ImageService3","width":1418,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"921.0,0.0 920.6,76.4 1417.2,74.7 1418.0,571.2 1177.0,572.0 1182.0,1070.7 968.6,1071.7 968.6,1567.2 1187.1,1566.6 1194.0,2126.0 423.8,2126.0 383.4,0.0 921.0,0.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.71658511906165,41.69893015832031]}},{"type":"Feature","properties":{"resourceCoords":[1418.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.709658981867,41.699018937656994]}},{"type":"Feature","properties":{"resourceCoords":[1418.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7094819702962,41.69121029788458]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.71640810749085,41.691121518547895]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p61","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0061/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0061","type":"ImageService3","width":1418,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"207.8,814.0 453.5,813.2 448.3,379.9 696.2,376.8 698.2,317.1 1191.7,315.4 1200.6,1803.3 1099.1,1803.6 1107.5,2126.0 833.7,2126.0 832.6,1804.3 710.7,1804.6 708.5,1594.6 462.9,1595.3 465.4,1805.2 -0.0,1806.4 -0.0,1312.2 212.9,1311.3 207.8,814.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.71187530454047,41.699887342662265]}},{"type":"Feature","properties":{"resourceCoords":[1418.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.70493021329641,41.69997701776411]}},{"type":"Feature","properties":{"resourceCoords":[1418.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7047514130627,41.692147125056714]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.71169650430676,41.692057449954866]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p62","metadata":[{"label":"streets","value":"9"},{"label":"intersections","value":"17"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0062/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0062","type":"ImageService3","width":1418,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1194.4,1810.8 183.2,1809.3 179.4,313.4 1184.3,313.1 1194.4,1810.8\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0062/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1188.0,812.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7010142,41.6970503]}},{"type":"Feature","properties":{"resourceCoords":[177.0,812.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7059739,41.6969746]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p63","metadata":[{"label":"streets","value":"8"},{"label":"intersections","value":"13"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0063/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0063","type":"ImageService3","width":1418,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"459.5,2090.2 461.4,1679.5 217.0,1674.1 230.2,99.3 1168.2,115.7 1169.1,0.0 1418.0,0.0 1418.0,2108.6 1333.5,2107.3 1333.2,2126.0 829.0,2126.0 829.6,2098.5 705.9,2095.8 459.5,2090.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0063/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[701.0,606.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6986741,41.6970754]}},{"type":"Feature","properties":{"resourceCoords":[969.0,1853.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6971348,41.6925229]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p64","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0064/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0064","type":"ImageService3","width":1418,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,2065.7 -0.0,124.0 173.8,124.6 173.4,54.3 930.4,56.2 931.3,126.9 1215.4,127.7 1214.8,56.9 1418.0,57.4 1418.0,2067.4 -0.0,2065.7\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0064/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.69203825897256,41.69917813729608]}},{"type":"Feature","properties":{"resourceCoords":[1418.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.68519002698274,41.699263690867866]}},{"type":"Feature","properties":{"resourceCoords":[1418.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.68501944628345,41.691542917973614]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.69186767827327,41.69145736440183]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p65","metadata":[{"label":"streets","value":"4"},{"label":"intersections","value":"3"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0065/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0065","type":"ImageService3","width":1418,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"208.2,415.8 695.4,415.9 691.7,0.0 1175.1,0.0 1178.0,416.1 1418.0,416.2 1418.0,1402.0 1195.3,1402.0 1207.3,2126.0 223.3,2126.0 208.2,415.8\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0065/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[704.0,1402.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7093727,41.6914362]}},{"type":"Feature","properties":{"resourceCoords":[215.0,1402.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7105897,41.6914178]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p67","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0067/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0067","type":"ImageService3","width":1418,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1200.9,2126.0 697.5,2126.0 704.3,1395.0 -0.0,1378.7 -0.0,386.7 1183.5,414.4 1167.8,1347.4 1214.2,1462.2 1200.9,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.70638147780716,41.69402811124168]}},{"type":"Feature","properties":{"resourceCoords":[1418.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.70290123323637,41.69414134619173]}},{"type":"Feature","properties":{"resourceCoords":[1418.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.70267547147002,41.69021748241427]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.7061557160408,41.69010424746422]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p68","metadata":[{"label":"streets","value":"4"},{"label":"intersections","value":"3"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0068/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0068","type":"ImageService3","width":1420,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"713.1,2126.0 706.2,1385.2 203.1,1385.3 173.9,1327.4 168.0,400.0 1192.2,401.9 1205.0,2126.0 713.1,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0068/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[683.0,400.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7021506,41.6933768]}},{"type":"Feature","properties":{"resourceCoords":[168.0,400.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7034329,41.6933577]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p69","metadata":[{"label":"streets","value":"4"},{"label":"intersections","value":"4"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0069/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0069","type":"ImageService3","width":1420,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"694.2,1814.0 203.0,1814.0 206.9,2126.0 -0.0,2126.0 -0.0,1572.7 199.7,1571.3 177.9,0.0 666.2,0.0 680.6,820.5 1023.2,820.6 1032.0,2126.0 698.7,2126.0 694.2,1814.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0069/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1186.0,1814.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6983233,41.6897659]}},{"type":"Feature","properties":{"resourceCoords":[203.0,1814.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7007493,41.6897417]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p7","metadata":[{"label":"streets","value":"7"},{"label":"intersections","value":"9"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0007/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0007","type":"ImageService3","width":1420,"height":2127},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1253.5,1949.0 -0.0,1948.5 -0.0,24.4 274.7,175.8 1349.3,267.1 1253.5,1949.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0007/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1254.0,1949.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6646511,41.6900766]}},{"type":"Feature","properties":{"resourceCoords":[120.0,1949.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.667239,41.6909006]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p70","metadata":[{"label":"streets","value":"6"},{"label":"intersections","value":"7"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0070/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0070","type":"ImageService3","width":1415,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"633.0,1804.0 393.3,1802.3 391.2,2116.9 -0.0,2114.3 -0.0,798.2 400.0,801.0 399.6,856.3 1415.0,829.1 1415.0,1142.5 1065.7,1146.2 1070.8,2126.0 636.2,2126.0 633.0,1804.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0070/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[673.0,302.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6971348,41.6925229]}},{"type":"Feature","properties":{"resourceCoords":[633.0,1804.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.697159,41.6897775]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p71","metadata":[{"label":"streets","value":"7"},{"label":"intersections","value":"9"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0071/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0071","type":"ImageService3","width":1418,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"206.4,2126.0 207.1,1921.1 -0.0,1917.5 -0.0,70.4 207.6,73.3 207.0,379.6 705.0,384.9 702.9,18.3 1092.1,0.0 1092.3,22.4 1194.5,23.6 1194.8,2012.5 697.7,2007.2 698.1,2126.0 206.4,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0071/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[207.0,774.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7104722,41.6886255]}},{"type":"Feature","properties":{"resourceCoords":[207.0,2002.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7102847,41.6841203]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p72","metadata":[{"label":"streets","value":"10"},{"label":"intersections","value":"22"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0072/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0072","type":"ImageService3","width":1418,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1418.0,2020.2 1418.0,2126.0 434.4,2126.0 434.6,2012.0 192.6,2010.2 186.6,13.0 437.5,15.0 439.5,384.5 692.1,383.1 684.3,17.0 940.3,19.0 940.7,395.8 1090.2,397.0 1086.1,675.8 1190.4,677.4 1187.6,2017.8 1418.0,2020.2\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0072/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1189.0,1382.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7006391,41.6865923]}},{"type":"Feature","properties":{"resourceCoords":[691.0,2014.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7029886,41.6842318]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p73","metadata":[{"label":"streets","value":"10"},{"label":"intersections","value":"33"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0073/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0073","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,1904.0 436.1,1905.1 436.4,1800.1 207.8,1797.2 214.8,311.2 460.5,315.5 460.1,471.5 820.9,477.8 823.6,321.8 942.5,323.9 942.4,483.6 1158.0,485.9 1160.7,0.0 1416.0,0.0 1416.0,2126.0 -0.0,2126.0 -0.0,1904.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0073/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[585.0,1802.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6986975,41.684294]}},{"type":"Feature","properties":{"resourceCoords":[459.0,810.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6994694,41.6879327]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p74","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0074/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0074","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1167.8,593.6 978.7,592.6 959.0,2126.0 -0.0,2126.0 -0.0,-0.0 986.3,3.9 985.1,92.9 1172.7,94.1 1167.8,593.6\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0074/gcps","type":"FeatureCollection","transformation":{"type":"polynomial","options":{"order":1}},"features":[{"type":"Feature","properties":{"resourceCoords":[0.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.72087637582477,41.68427751826436]}},{"type":"Feature","properties":{"resourceCoords":[1416.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.71396770323662,41.68441488567382]}},{"type":"Feature","properties":{"resourceCoords":[1416.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.71369349044157,41.67661316103894]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.72060216302972,41.67647579362948]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p75","metadata":[{"label":"streets","value":"10"},{"label":"intersections","value":"41"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0075/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0075","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1416.0,197.4 1416.0,813.9 995.6,816.5 998.9,1065.4 1178.8,1052.4 1185.5,1066.4 1198.7,1547.8 1005.4,1551.0 1011.8,2039.7 1166.2,2038.5 1167.6,2117.9 -0.0,2126.0 -0.0,580.4 184.9,579.0 183.5,86.5 -0.0,87.8 -0.0,-0.0 1156.0,0.0 1158.8,201.9 1416.0,197.4\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0075/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[936.0,1066.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7113224,41.6804366]}},{"type":"Feature","properties":{"resourceCoords":[192.0,1066.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7150342,41.6803992]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p76","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0076/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0076","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"198.1,1547.0 191.1,1057.6 184.3,1043.3 -0.0,1054.0 -0.0,801.0 430.6,804.1 438.9,177.6 671.9,176.7 670.9,57.7 1416.0,62.6 1416.0,2126.0 158.5,2126.0 158.2,2045.3 -0.0,2044.3 -0.0,1547.6 198.1,1547.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.71114663536356,41.684302249232125]}},{"type":"Feature","properties":{"resourceCoords":[1416.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.70425151662747,41.684441849591984]}},{"type":"Feature","properties":{"resourceCoords":[1416.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.70397284625044,41.67665543551444]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.71086796498653,41.67651583515458]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p77","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0077/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0077","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1416.0,2126.0 -0.0,2126.0 -0.0,43.9 1416.0,59.5 1416.0,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.69196455167743,41.691836072549656]}},{"type":"Feature","properties":{"resourceCoords":[1416.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.68507248069386,41.69197299183034]}},{"type":"Feature","properties":{"resourceCoords":[1416.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.68479913018965,41.684190933441954]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2126.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.69169120117321,41.68405401416127]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p78","metadata":[{"label":"streets","value":"9"},{"label":"intersections","value":"23"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0078/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0078","type":"ImageService3","width":1416,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,555.9 415.8,0.0 598.9,0.0 1033.0,79.5 1197.8,432.4 1209.3,595.0 1201.8,1384.5 1182.0,2063.4 1008.1,2106.6 1007.7,2126.0 430.6,2126.0 -0.0,2045.9 -0.0,555.9\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0078/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[933.0,617.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6823886,41.6898079]}},{"type":"Feature","properties":{"resourceCoords":[681.0,2056.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6833945,41.6845003]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p8","metadata":[{"label":"streets","value":"7"},{"label":"intersections","value":"8"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0008/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0008","type":"ImageService3","width":1420,"height":2127},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"43.3,1938.4 185.1,262.9 607.5,305.5 691.8,498.6 947.4,390.1 984.9,0.0 1420.0,0.0 1420.0,1855.3 1240.0,1928.8 1260.0,2127.0 702.4,2127.0 707.5,1956.2 43.3,1938.4\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0008/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[636.0,1304.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6627014,41.6907688]}},{"type":"Feature","properties":{"resourceCoords":[996.0,1964.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6624704,41.6893835]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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_066 p9","metadata":[{"label":"streets","value":"0"},{"label":"intersections","value":"0"}],"created":"2026-09-21T21:26:15Z","modified":"2026-09-21T21:26:15Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0009/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_1950-0009","type":"ImageService3","width":1420,"height":2127},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"219.2,599.3 573.6,0.0 1132.2,0.0 1167.8,71.8 1225.0,103.5 1035.7,79.8 991.2,977.6 1018.9,979.0 1357.4,2127.0 381.4,2127.0 141.1,1128.8 219.2,599.3\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790195049:01790_49_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":[-87.67118078175233,41.694069164361956]}},{"type":"Feature","properties":{"resourceCoords":[1420.0,0.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.66794723839836,41.69310793734463]}},{"type":"Feature","properties":{"resourceCoords":[1420.0,2127.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.66986187213975,41.68946562454425]}},{"type":"Feature","properties":{"resourceCoords":[0.0,2127.0],"type":"corner"},"geometry":{"type":"Point","coordinates":[-87.67309541549372,41.690426851561575]}}]}}]}