SANBORN MAPS OF JAFFREY
Sanborn maps are detailed maps of U.S. cities and towns in the 19th and 20th centuries. Originally published by The Sanborn Map Company, the maps were created to allow fire insurance companies to assess their total liability in urbanized areas of the United States. Since they contain detailed information about properties and individual buildings in approximately 12,000 U.S. cities and towns, Sanborn maps are valuable for documenting changes in the built environment of American cities over many decades.
Sanborn held a monopoly over fire insurance maps for the majority of the 20th century, but the business declined as US insurance companies stopped using maps for underwriting in the 1960s. The last Sanborn fire maps were published on microfilm in 1977, but old Sanborn maps remain useful for historical research into urban geography. The license for the maps was acquired by land data company Environmental Data Resources (EDR), and EDR was acquired in 2019 by real estate services company LightBox.
The Sanborn maps themselves are large-scale lithographed street plans at a scale of 50 feet to one inch (1:600) on 21 by 25 inches (53 by 64 cm) sheets of paper. The maps were published in volumes, bound and then updated until the subsequent volume was produced. Larger cities would be covered by multiple volumes of maps. Between editions of published volumes, map updates were sent out as correction slips. Sanborn employees, called "pasters" or "correctors", would visit subscribers' offices to paste the slips on top of the old maps.
The map volumes contain an enormous amount of information. They are organized as follows: a decorative title page; an index of streets and addresses; a ‘specials’ index with the names of churches, schools, businesses etc.; and a master index indicating the entirety of the mapped area and the sheet numbers for each large-scale map (usually depicting four to six blocks); and general information such as population, economy and prevailing wind direction.
The maps include outlines of each building and outbuilding; the location of windows and doors; street names; street and sidewalk widths; property boundaries; fire walls; natural features (rivers, canals, etc.); railroad corridors; building use (sometimes even particular room uses); house and block number; as well as the composition of building materials including the framing, flooring, and roofing materials; the strength of the local fire department; indications of sprinkler systems; locations of fire hydrants; location of water and gas mains; and even the names of most public buildings, churches and businesses.
Unique information includes the location of the homes of prominent individuals, brothels, and more ephemeral buildings including outhouses and stables.
—Wikipedia
The source of the Sanborn maps included here is the Evans Map Room at Dartmouth College. See https://www.library.dartmouth.edu/digital/digital-collections/sanborn-fire-insurance-maps-new-hampshire-towns-1880s-1940s
Sanborn Maps 1911