I always talk about back when things were simple, but actually some things weren’t that simple. Insurance companies writing policies on property many years ago needed some way to record what they were insuring. Photographs were pretty advanced already in the beginning of the 1900’s, for instance, but making a book to show properties was simpler to just do by hand.
The Sanborn Map Company, who made the maps we have, is still in existence. http://www.sanborn.com/products/fims The sample maps on their website are quite a bit more complicated than they were in the 1920’s.
At Shippensburg Historical Society, http://www.shippensburghistory.org/ we have books of the insurance maps of the town from the years 1929 and 1936. They are fascinating books that divide the town into sections and show what buildings existed at that time. There is a key in each book that gives the details of what the maps show: what each building was made of, the number of stories, what the roof was made of, how far the building was from a fire station, and a few more details. Distance from a fire station mattered in writing insurance, as did construction: bricks being more fire safe than wood frame, and tin or slate roofs being harder to catch fire than any type of flammable shingles.
My property is shown here, and also shows that there was a house on my lot beside my house. I know that that house was torn down some time after 1936, since the map shows it still existing in the 1936 book. I don’t know any more about that house, but I will after I do more digging, cos I want to know more.
These books contained some information about the town in general as well, again for insurance purposes and getting around in case of fires: condition of the streets, availability of water, even prevailing winds.
Fascinating stuff, history. I never knew such information existed until a couple of years ago. If you like to learn about history, you should check out your local historical society and see what kinds of interesting looks into your past they can show you.