PRIMARY SOURCE TRAIL This shelf is intended to be a starting point, not a substitute for the collections themselves. Open the scans. Read the catalog records. Follow the references and preserve uncertainty where the source does not answer a question. MAPS AND CARTOGRAPHY Library of Congress, Map of the Great Tartary https://www.loc.gov/resource/wdl.15038/ Library of Congress, Abraham Ortelius map guide https://guides.loc.gov/abraham-ortelius/featured-selection-of-maps David Rumsey Historical Map Collection https://www.davidrumsey.com/ Mark C. Elliott, The Limits of Tartary https://doi.org/10.2307/2658945 ARCHITECTURE AND ENGINEERING Chicago Water Tower, Historic American Buildings Survey, Library of Congress https://www.loc.gov/item/il0097/ Brooklyn Bridge specifications, Library of Congress https://www.loc.gov/item/2007570228/ Brooklyn Bridge, American Society of Civil Engineers https://www.asce.org/about-civil-engineering/history-and-heritage/historic-landmarks/brooklyn-bridge/ Encyclopedia of Chicago, Construction https://www.encyclopedia.chicagohistory.org/pages/331.html CHICAGO GRADE CHANGES Street Raising on Lake Street, Encyclopedia of Chicago https://www.encyclopedia.chicagohistory.org/pages/3292.html Multicentered Chicago, Encyclopedia of Chicago https://www.encyclopedia.chicagohistory.org/pages/854.html Ellis Sylvester Chesbrough, ASCE https://www.asce.org/about-civil-engineering/history-and-heritage/notable-civil-engineers/ellis-sylvester-chesbrough/ SEATTLE REGRADE Seattle Municipal Archives, A City at Work https://www.seattle.gov/city-archives/exhibits-and-education/online-exhibits/a-city-at-work Denny Hill Regrade Photograph Albums https://archives.seattle.gov/finding-aids/repositories/2/resources/451 WORLD'S FAIRS Library of Congress, Chicago in 1893: Selected Maps https://blogs.loc.gov/maps/2024/12/chicago-worlds-fair-selected-maps/ Official Directory of the World's Columbian Exposition https://www.loc.gov/resource/gdcmassbookdig.officialdirector00worl/?st=gallery Smithsonian Institution Archives, Exposition Records https://siarchives.si.edu/collections/siris_arc_216677 STAR FORTS AND CHILD WELFARE National Park Service, Bastions at Castillo de San Marcos https://www.nps.gov/casa/learn/historyculture/bastions.htm Library of Congress, A Treatise on Field Fortification, 1860 https://www.loc.gov/resource/gdcmassbookdig.treatiseonfieldf00maha_0/?st=gallery Library of Congress scan discussing orphan trains and child welfare history https://tile.loc.gov/storage-services/master/gdc/gdcebookspublic/20/21/75/86/21/2021758621/2021758621.pdf SOURCE RULE Wikipedia, modern blogs and conspiracy sites can help locate a lead. They should not be the final authority when an archive, survey, official report, book scan or scholarly article is available. A claim about a map should lead to the map. A claim about a building should lead to the building record. A claim about a city project should lead to the city record.