Palimpsest of the Map: Towards a History of the Sanborn Map Company

28 Feb. 2018

Jack Swab (M.A. candidate in Geography) gave a presentation on his Master's thesis project about the Sanborn Map Company in preparation for the American Association of Geographer's Conference, which takes place in April.

Palimpsest of the Map: Towards a History of the Sanborn Map Company

Sanborn Fire Insurance Maps are a ubiquitous part of the American historical record, with almost 700,000 maps on depository at the Library of Congress alone. Frequently used by historians, genealogist, geographers, and environmental engineering firms as snapshots of past urban landscapes, these maps are a significant source of historical and geographical information. Interestingly, beyond the maps themselves, information about their construction, circulation, and larger impacts on the American built environment is relatively unknown.  

While many Sanborn maps (updated via "pasted-on" corrections) in of themselves are palimpsest or can be turned into palimpsests with modern digital tools, this paper takes a different approach. Here the concept of palimpsest is used as a tool to trace and recreate the historical “informational landscape” of Sanborn maps. The argument here is that these maps, as tools of spatial inquiry, were far more ubiquitous than previously thought and that the relative rarity of these maps are reflective of the larger processes to control and monetize geographic information in the 19th and 20th centuries.  

This presentation also touched upon later efforts by the Sanborn Map Company to provide customized products for American urban planning departments.