|Map Librarian Doug Magee|
"Sanborn maps were made to assist insurance underwriters in determining fire insurance rates for individual buildings by examining the buildings' construction methods, heat and lighting sources, manufacturing uses, and the same attributes of nearby buildings. The maps primarily provide information on the downtown areas of cities and adjoining residential areas. They are especially useful in providing a record of urban development from the 1880s through the first half of the twentieth century."
Doug presented a slide show that can be used to gain a better understanding of the symbols that are used on the maps.
1887 was the first year that Sanborn maps were published for Cincinnati. They have limited value for identifying a specific home because house numbers were not included on the map. In addition, the streets of Cincinnati were renumbered in the early 1890s and some street names were changed. The cost of publishing the maps with any kind of frequency was prohibitive, so changes in the forms of cut-outs were provided that could be glued on top of the original map. Since there is no indication for when these changes took place, the maps do not have as much historical value as they could have had.
We learned that the Sanborn Map of Cincinnati for 1922 is significant because it was not updated and included all of the areas within the city limit. In addition, there are two index books kept at the Genealogy and Local History desk that are invaluable when used in conjunction with the 1922 maps. The first book is an index listing all of the real estate values for Hamilton County, and the second is a 2-volume Index of Property Owners, Real Estate Atlas of Cincinnati, 1922.
site. Included are the long-awaited records of the Baltimore Pike Cemetery.
There is also a digitized version of the 1892 Decennial Tax Valuation of Cincinnati online. It can be downloaded from the Virtual Library from the Old and Rare Books section (R336.220977 C574 1892).
Finally, I was made aware of the numerous indexes published by William H. Graver, including an index to property ownership maps. Just when I was beginning to think that I was pretty familiar with some of the resources available at our library, I found out that I haven't even begun to scratch the surface. Happy hunting!
Note: To view the Cincinnati Sanborn Fire Maps online, click on this link.