More than maps, history

Posted 11/19/20

They are beautiful in their detail and exactness. The Sanborn Map Company’s fire insurance maps were never intended as such, but they are works of art. 

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More than maps, history


They are beautiful in their detail and exactness. The Sanborn Map Company’s fire insurance maps were never intended as such, but they are works of art. 

The Library of Congress holds the largest collection of Sanborn maps. The collection contains 1,599 maps of Texas cities, including Mineola and Winnsboro. The Meredith Memorial Library holds a number of the Mineola maps, from 1885 to 1922. Additional holdings exist in the Perry-Castaneda map collection at the University of Texas and in the Texas State Library and Archives Commission.

From the company’s founding in 1867 to 1950 – the year they last published a catalog of their maps – the company documented the development of the nation. 

With a small army of surveyors and hundreds of production assistants, the company produced highly accurate, descriptive maps of American cities. Those maps possessed a richness of detail which is inspiring to consider. 

Surveyors arrived to their assigned locations with little but pencil and notepad. Their assignment was to produce the most accurate map of all city features which, in summation, could be used to underwrite that municipality for fire insurance. 

The issuing of fire insurance in the United States dates back to colonial days. The first recorded fire insurance map on the continent was produced by a British mapping firm in the late 18th century for the city of Charleston, S.C. 

It was however the massively-destructive 1835 fire in New York City, which came to be known simply as the New York conflagration, that changed the industry of fire insurance. 

The conflagration put many small insurers out of business. Regulation of the fire insurance industry followed. Two things emerged from the ashes: a small number of large, financially-resourced fire insurance companies and the need for some method by which to judge a city’s fire risk.

That necessity to judge fire readiness prompted the growth of fire insurance mapping. 

A trained surveyor, Daniel A. Sanborn’s first work of consequence was the 1866 insurance map of Boston. His subsequent work on behalf of the Aetna Insurance Company led him to conclude that a systematic and standardized mapping of American cities was a national requirement.

He founded the D.A. Sanborn National Insurance Diagram Bureau in 1867 and embarked on the adventure of mapping the nation. As all new firms, the first decade was a struggle, but driven by Sanborn’s insistence on producing only the highest quality, the company flourished. 

In the first year the company produced 50 single-sheet maps. Within ten years over 1,000 cities were mapped. By Sanborn’s death in 1883, almost 2,000 cities were being mapped. A copyrighted mapping key was developed. 

In 1905 Sanborn printed a thorough surveyor’s manual describing the processes involved in compiling their mapping data. The number of maps in their catalog increased steadily. By the 60th anniversary of their founding, the company maintained over 13,000 cities, 365 of which required bound volumes of over 100 individual mapping sheets.  

A Central Department in Chicago and a Pacific Department in San Francisco were added, with the headquarters located in Pelham, N.Y. Production reached its peak in the 1930’s. Post-World War Two technological developments led to a decrease in demand, and the company began to evolve in the second half of the 20th century. The hey-day of the Sanborn fire maps had passed. 

The company, however, not only survived, it has blossomed into one of the world leaders in global mapping. Field surveyors were largely replaced by remote sensors, satellites and technologies such as LIDAR (light detection and ranging).

These 21st century technologies can produce imagery with a variety of sensors in resolutions down to inches. Other adaptable techniques are employed to meet the ever-growing thirst for physical mapping. For instance, compensation for the curvature of the earth and rectification of local elevation differences are combined with sensor data to produce orthophotography. 

Mobile mapping capabilities which use LIDAR technology can produce near instantaneous 3D visualization.   

Such products are in great demand. Practically all industries involved in the physical realm are potential customers. From mining and agriculture, to conservation and construction, to city planning and national defense, Sanborn customers are worldwide and diverse. 

A most interesting aspect of Sanborn’s present portfolio is the mating of high-resolution imagery with near real time emergency response. The safety and security applications of this relationship are limitless.

Sanborn yet maintains a modern set of maps for 40 major U.S. cities. They are based on the most advanced mapping data available. As Jason Caldwell, vice president of business development confirmed, the present city data-sets are today’s version of the original Sanborn fire insurance maps.

Through the years, Sanborn Map Company has built an intense company loyalty among its employees. In the early 20th century, when labor unrest and appalling working conditions were not uncommon, Sanborn was generations ahead in employee relations. The company published a monthly newsletter containing employee input, as well as employee recognition, anecdotes and features about how to increase efficiency. The May 1926 newsletter was 15 pages.

It is said that when the company finally did have to downsize at the end of the paper map era, many long-time employees simply did not leave the building. The surveyors numbered approximately 400 at the apex of production, with 300 employees involved in coloring, gluing, printing and binding.  

They produced some treasures. Today, the original maps are important sources for historians, genealogists and cities rebuilding older sections of town. Reviewing a 1922 Sanborn map of Mineola revealed the location of the original Catholic Church on S. Johnson St. An earlier Sanborn map disclosed the location of a water well under M Prints Printing.

The Mineola library’s maps are plasticized to protect the 20” x 25” documents, but the beauty of these maps is not diminished. As was noted in a 1926 booklet published by the company to celebrate its 60th anniversary, “Although whenever practicable, modern machinery and processes are utilized, the making of our maps is still one of the ancient arts, in which the soul of the craftsman finds inspiration and expression.”