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Introduction to the Sanborn Map Collection

(This article was published within the Library's publication, Fire Insurance Maps: in the Library of Congress)

Key symbols used with fire insurance maps
Key for interpreting Sanborn
fire insurance maps

The Sanborn map collection consists of a uniform series of large-scale maps, dating from 1867 to the present and depicting the commercial, industrial, and residential sections of some twelve thousand cities and towns in the United States, Canada, and Mexico. The maps were designed to assist fire insurance agents in determining the degree of hazard associated with a particular property and therefore show the size, shape, and construction of dwellings, commercial buildings, and factories as well as fire walls, locations of windows and doors, sprinkler systems, and types of roofs. The maps also indicate widths and names of streets, property boundaries, building use, and house and block numbers.

The Sanborn collection includes some fifty thousand editions of fire insurance maps comprising an estimated seven hundred thousand individual sheets. The Library of Congress holdings represent the largest extant collection of maps produced by the Sanborn Map Company.

During the past century the Sanborn Map Company has published maps and atlases of more than twelve thousand United States towns and cities, issued in some seven hundred thousand separate sheets, and yet the name Sanborn is known to but a small number of American map users. This anomalous situation has persisted because Sanborn's specialized maps were prepared for the exclusive use of fire insurance companies and underwriters.

Insurance maps and plans originated in London toward the end of the eighteenth century in response to the need felt by large fire insurance companies and underwriters for accurate, current, and detailed information about the buildings they were insuring. Thomas Leverton is credited with having produced a map of central London for the Phoenix Assurance Company, Ltd., around 1785 but the Phoenix Company, which is still in business, has no record of such a map having been prepared. Between 1792 and 1799, however, we know Richard Horwood compiled for Phoenix a map of London at the scale of 26 inches to a mile. A copy of it is in the Library of Congress collections. This large-scale detailed map, which is on thirty-two sheets, identifies by street number every dwelling and commercial structure then standing. Horwood dedicated his map "to the Trustees and Directors of the Phoenix Fire Office."

During the period from around 1785 to 1820 or later, Phoenix extended its insurance coverage to buildings in the West Indies, Canada, and the United States, where the company sponsored surveys of several American cities. The earliest extant insurance map is a plan of Charleston, South Carolina, published in 1790 from a survey made in August 1788 by Edmund Petrie. It is titled Ichonography of Charleston, South Carolina, At the request of Adam Sunno, Esq. for the use of the Phoenix Fire-Company of London, Taken from Actual Survey, 2d August 1788 by Edmund Petrie. Published 1stJany. 1790 by E. Petrie No. 13 America Square. The plan, which is at the scale of 400 feet to an inch, identifies public buildings, churches, wharves, business establishments, streets, and public and private wells by numbers or letters and notes that there are "9 Fire Engines belonging to the City."

In a letter dated October 19, 1973, Graham M. Hayward, museum curator of the Phoenix Assurance Company, Ltd., notes that a committee was "formed on the 4th October 1786 to procure plans of towns abroad. The only reference to one acquired for an American city is dated the 5th November 1788 when it was resolved at the Board meeting of that day 'that One Hundred Guineas be paid for the Plan of Charleston-and that Mr. Sunno be requested to transmit the same to the Person who executed the Plan'." 1. Hayward adds that:

unfortunately, the old minute books were not indexed at the time the minutes were written up and this is the only reference I can find therein to a map of any town in the U.S.A. . . . It is of interest to record the [Phoenix's] first acceptance of an American Colony risk was dated the 10th August 1785 and covered the buildings of Mr. Pointsett, in Charles Town.' Further, on the 5th August 1789 an engine, prepared with suitable inscriptions, was sent to Charleston, South Carolina, as a present to the Union Fire Club of that City. At the Board meeting held on the 9th February 1790 a letter was read from a Mr. H. Grant, President of that Club, acknowledging the receipt of the engine presented to the City. A second engine was sent, following the Board meeting held on the 5th May 1802. 2

Edmund Petrie's plan of Charleston, South Carolina, published in 1790.
Edmund Petrie's plan of Charleston,
South Carolina, published in 1790.

Hayward reports further that "in September 1807, Mr. Jenkin Jones Secretary of the [Phoenix] company from 1st May 1805, until his death in April 1837 (and also Assistant Director from April 1833) was requested by the Board of Directors to undertake a tour to obtain accurate topographical information relative to the several West India Islands, and the principal Cities and Towns in the States of North America so far as they may be applicable to Fire Insurance'." 3

Among the United States cities visited by Jones were New York, Albany, Boston, Philadelphia, Baltimore, and Washington; Norfolk, Richmond, and Petersburg, Virginia; Raleigh, Fayetteville, and Wilmington, North Carolina; and Charleston and Savannah. Jones's letters and reports on the twenty-one-month trip are preserved in a two hundred-page bound collection. His report on his visit to Philadelphia on October 28, 1808, reads: "Made a detailed survey and plan. The streets universally at right angles and of a handsome breadth. No city in America, not perhaps in England, has been so exempted from conflagration. About 40 engines in operation, besides pumps and wells." 4

The Jones report stated that surveys had been made of several other cities, but regrettably the resulting maps and plans have not survived either in the Phoenix archives or in the collections of the Library of Congress's Geography and Map Division. Jones commented in several of his entries about the deteriorating relations between Great Britain and the United States. His September 5, 1808, report from Boston notes "political feeling very strong. The embargo becomes more and more unpopular in this part of the Union, and the general current of the elections to the new Congress will in all prospect be favourable to English interests; but whether the Federalists will obtain a majority sufficient for its repeal, may be reasonably doubted." 5 Following the congressional elections Jones reported, on December 2, 1808, that "the ambiguity of the President on the opening of Congress excited a great sensation. The scene, however, has since cleared up and it is now pretty well ascertained that we are not to have war, at least not from this side of the water." 6 Jones's report also listed the Phoenix Company's policies in the United States at the time, which numbered almost eight hundred, with insurance coverage exceeding four and a half million dollars. Phoenix was undoubtedly the major English fire insurance company operating in America.

Jenkin Jones was, in general, favorably impressed with fire protection in the major cities. In New York, for example, he found, "admirable provisions for the extinguishing of fires," with facilities "superior to London." With reference to New York he concluded, on June 16, 1808, that "should not a war take place (and I am sanguine it will not, from the singular unpopularity into which the present American administration have fallen, from their hasty measures of an embargo) that the [Phoenix] Company may be placed upon a footing to ensure a considerable and a profitable business." 7

Notwithstanding Jones's optimistic hope, war was declared between Great Britain and the United States in 1812. The war was unpopular in both countries and engendered considerable ill will in both England and America toward the respective enemy nation. The Treaty of Ghent in 1815 was quite ambiguous and left many unresolved problems. Cessation of hostilities was, however, welcomed by both countries, the fact that American manufacturing, industry, and commerce prospered during the war because of the embargo on British goods notwithstanding. Many commercial and financial ties with Great Britain had been severed and Americans began to look increasingly to their own resources.

Although a fire insurance company was established in Philadelphia as early as 1752, the number of domestic companies was quite limited before the War of 1812. Both before and immediately after the Revolution, London fire underwriters wrote most of the fire insurance for buildings in American cities. Animosity toward the British grew more intense during the War of 1812, and this feeling plus restrictions on foreign companies operating in the United States encouraged existing American companies to expand their activities and stimulated the formation of new companies. The postwar increase in population, the healthy state of business, the growth of cities, and the accumulation of capital in the United States offered further inducements. New York, Philadelphia, Boston, and Hartford became the principal fire insurance centers.

Until 1835 American companies were run largely by local merchants as personal or partnership enterprises, and they solicited business primarily in their immediate environs. Personal inspection of the risk properties was possible, so there was little need for special insurance maps. The few fire insurance maps available were of a general nature, such as The Fireman's Guide, a Map of the City of New-York Showing the Fire Districts, Fire Limits, Hydrants, Public Cisterns, Stations of Engines, Hooks & Ladders, Hose Carts &c. which was published in 1834 by P. Desobry.

In 1835 a major conflagration in New York City caused losses of more than 20 million dollars and wiped out most of the nation's smaller insurance companies, which had little or no reserve funds. In the reorganization of the industry larger companies were formed, and states and cities passed laws requiring reserve funds and issued other regulations. Solicitation areas were expanded by the larger companies, which maintained agents in various cities. Personal inspection of properties under consideration for insurance became impossible and a demand for maps giving essential risk information developed.

George T. Hope is generally credited with having fostered the idea of specialized and detailed fire insurance maps in the United States. Around 1849 or 1850, Hope, who was at the time secretary of the Jefferson Insurance Company in New York City, began to compile a large-scale map of a portion of New York City for use in calculating fire risks on business and residential structures. He engaged William Perris, an engineer trained in England, to make the surveys and draft a map of the city from the lower tip of Manhattan Island to Twenty-second Street. To ensure that the proposed map would include all essential information, Hope formed a committee of fire insurance officials, with himself as chairman, to direct the project. The committee agreed that the map should identify the construction materials in all buildings by a system of colors, formulated a set of appropriate cartographic symbols, and agreed on a format and a scale for the map. The standards adopted by the Hope committee were followed, with few modifications, for a century or more.

In the Library's Geography and Map Division there are twelve plates (68 by 90 cm) of the Hope-Perris map, at the scale of 50 feet to an inch. They are numbered from thirteen to twenty-four and show the Seventh, Tenth, and Thirteenth Wards. The sheet credits indicate that they were "published by William Perris and Augustus Kurth" and lithographically reproduced by Korff Brothers of 30 Cedar Street. It is not known whether plates one through twelve of this series were ever published.

The Geography and Map Division collections also include seven bound volumes published by William Perris between 1852 and 1855 under the general title Maps of the City of New York Surveyed under Directions of Insurance Companies of Said City. Perris also published revised editions to 1859. Subsequent volumes dating from 1860 to 1889 carry the imprint of Perris & Browne, son and son-in-law of William Perris. An 1859 atlas of Newark, New Jersey, was also published by Perris and Browne.

The 1852 Hope-Perris map of New York City appears to be the earliest large-scale map published specifically for use by fire insurance underwriters. In the late 1840s and early 1850s, however, a number of large-scale detailed maps and plans of American cities had been published. Many of them included information useful to the fire insurance industry, such as block dimensions and configuration of buildings, width of streets, fire districts, hydrants, and fire stations. Among them is the Map of the City of New York Extending Northward to Fiftieth Street, surveyed and drawn by John F. Harrison and published in 1851 by M. Dripps of New York City. The map, which is in four sheets and at the scale of 300 feet to an inch, was lithographically printed by Kollner, Camp & Company of Philadelphia. Another such map, an anomaly because it was reproduced from engraved copper plates, is a nine-sheet map of St. Louis, at the scale of 500 feet to an inch, which was published in 1852 by Leffingwell & Elliott. It was surveyed by Edward Charles Schultz and the engraver was J. H. Fisher. A revised edition of Leffingwell's map was published in 1859. Although it still credits J. H. Fisher as engraver, the map appears to have been printed on a lithographic press and was colored manually.

Engraving as a medium for reproducing maps had been generally superseded by lithography by 1850. In fact, the application of lithographic techniques to map reproduction played a major role in the acceleration of map publishing in the United States in the last half of the nineteenth century. The demands for fire insurance maps and other specialized cartographic formats could not have been met if lithographic printing had not been available at the time.8

Impressed by the utility and acceptance of the Perris and Browne map series, other surveyors, publishers, and insurance companies ventured into insurance cartography. William H. Martin prepared a series of manuscript fire insurance plans of cities and towns for the Aetna Fire Insurance Company as early as 1855.9 In 1856 an insurance map reportedly was registered for copyright by J. B. Bennett, manager of Aetna's Cincinnati office.10 No copy of this map has, however, been found in the Library of Congress Geography and Map Division, principal repository for copyrighted maps.

Ernest Hexamer and William Locher introduced a series of insurance maps of Philadelphia in 1857. Their series was continued, with enlargements, until 1915, when the Hexamer and Sanborn companies merged. The Hexamer series is at the same scale (50 feet to an inch) as the Perris and Sanborn maps, and similar symbols are used. In the collections of the Geography and Map Division there are editions of Hexamer atlases dating from 1857 to 1915. Also in the collections is the title page, table of symbols, and sample sheet of volume one of Maps of the City of Philadelphia, surveyed by Ernest Hexamer and William Locher. The Library's copy was registered and deposited for copyright in 1857.

In 1859 Western Bascome, Ins. Agt. & Adjuster, and John A. Parr, Surveyor and Draftsman, copyrighted a two-sheet Fire Insurance Map of St. Louis, Missouri. An "Explanation of Marks" is reproduced at the top of the second sheet. The map is at the scale of 70 feet to an inch, and type of material in buildings is indicated by hand-applied colors.

The Civil War restricted insurance map publishing as well as other branches of nonofficial cartography. The several decades following the war, however, were prosperous ones, particularly for the eastern, middle Atlantic, middle western, and far western states. Extension of railroad lines stimulated industrial and commercial growth, which contributed to urban development. Immigration during the sixties and seventies also augmented both rural and urban population. All these conditions nourished the youthful insurance map industry and induced a number of individuals and publishers to enter the field.

Boston, Massachusetts Vol. I 1867
Boston, Massachusetts
Vol. I 1867

D. A. Sanborn, a young surveyor from Somerville, Massachusetts, was engaged in 1866 by the Aetna Insurance Company to prepare insurance maps for several cities in Tennessee. Probably the maps he made were retained in manuscript copies in the Aetna files and were not published. No copies were registered or deposited for copyright and none are preserved in the Library of Congress. Before working for Aetna, Sanborn conducted surveys and compiled an atlas of the city of Boston titled Insurance Map of Boston, Volume 1, 1867. The title page reads "By D. A. Sanborn, C. E. 117 Broadway, New York." Also on the title page are symbols and an index map. The atlas includes twenty-nine large plates showing sections of Boston at the scale of 50 feet to an inch. It is believed to include the earliest insurance maps published by Sanborn.

The success of the Boston atlas and the commission from Aetna must have impressed the young surveyor with the importance of detailed and specialized maps for the fire insurance industry. Following his assignment in Tennessee for Aetna, he established the D. A. Sanborn National Insurance Diagram Bureau in New York City in 1867. 11 From this modest beginning grew the specialized company that has compiled and published maps for the fire insurance industry for more than a hundred years.

During the period 1865 to 1900 a number of surveyors and map publishers prepared fire insurance maps and atlases, but these were principally of urban areas in their immediate locale. New Jersey cities in particular seemed to invite such cartographic activity. Arnois, Spielman and Company, which subsequently merged with Charles B. Brush, issued insurance atlases of Hoboken, Jersey City, and Hudson County. Reimer and Olcott published an atlas of Orange, New Jersey, and Scarlett issued pertinent volumes for Essex and Mercer Counties, the Jersey coast, and the cities of Harrison and Kearny. From 1872 to 1873 William A. Miller published insurance maps of the New Jersey cities of Elizabeth, Paterson, Plainsfield, Rahway, Union, and West Hoboken.

Passaic, New Jersey October 1886, title sheet
Passaic, New Jersey
October 1886, title sheet
Midwest publishers of insurance atlases included Alphonso Whipple, who produced volumes for Missouri cities and Granite City, Illinois, and the Rascher Map Company, which issued a series for Chicago as well as for Detroit and Muskegon, Michigan; Duluth, Minnesota; and Kansas City, Missouri. All the above named companies had only brief productive periods and then either ceased publishing or were absorbed by the Sanborn Map Company.

D. A. Sanborn died in 1883. The company he founded, however, continued to grow. In 1899 it acquired the Perris and Browne firm and can by virtue of this expansion date its origins to 1852. The firm name established by Sanborn in 1867 was changed in 1876 when the firm was incorporated under the name Sanborn Map and Publishing Company, which then became the Sanborn Perris Map Company, Ltd., until, in 1902, the name was shortened to the Sanborn Map Company, the form which the company uses today.

The earliest Sanborn item in the Library of Congress is the Insurance Map of Boston, actually an atlas, published in 1867. The collections of the Geography and Map Division also include an 1868 map of Toledo, Ohio, in five sheets, with an accompanying sheet giving the population of the city, number of available fire engines, and other information of use to underwriters. There is a copyright registration notice on the descriptive form but not on the map sheets. The former carries the imprint of D. A. Sanborn National Insurance Diagram Bureau, 117 Broadway, New York City.

Also in the Library of Congress is a five-sheet map of Rutland Vermont, published by the Sanborn Map and Publishing Company, Limited, in October 1879. It carries no notice of copyright registration. The Rutland map was purchased in March 1929. All five sheets bear stamps of a previous owner, the Phoenix Assurance Company of London, the earliest company to use fire insurance maps.

There is further evidence of Sanborn's publishing activity before 1883 in Earl G. Swem's Maps Relating to Virginia in the Virginia State Library and Other Departments of the Commonwealth (Richmond, 1914), which describes some fourteen Sanborn maps of Virginia cities, published between 1872 and 1882.

Sanborn appears to have begun systematic registering of maps, with deposit copies, in 1883. With the exception of the Boston atlas, the 1868 map of Toledo, and the map of Rutland, Vermont, noted above, the sheets carrying the 1883 date are the earliest in the Library of Congress. Within the next two or three years deposit sheets were received for cities in virtually every state, suggesting that in the years immediately before and following incorporation in 1876 Sanborn had expanded its insurance map coverage to all parts of the United States. Although some of the growth resulted from absorption of other map companies, most of the expansion must be attributed to good managerial procedures and practices. The Sanborn Company successfully produced detailed, comprehensive, and up-to-date maps which met the needs of the fire insurance industry.

Sanborn surveyors were at work in all the states, and during the years of maximum production there were as many as three hundred employees in the field and more than four hundred in the main office and publishing plant in Pelham, New York, and in secondary production centers in Chicago and San Francisco.

Sanborn mapmakers worked anonymously, and their names never appeared on the maps they produced. Occasionally in a field man achieved fame and fortune in some subsequent activity. One such mapmaker was Daniel Carter Beard, who is remembered as naturalist, illustrator, author of books for boys, and one of the founders of the Boy Scouts of America. In his autobiography, published in 1939, Beard related how he joined the Sanborn Company in 1872. "My opportunity to travel came at last," he recalled, "and I left my then well paying position in the [Cincinnati] engineer's office to accept an appointment for a lesser amount as a surveyor for the Sanborn Map and Publishing Company. While working for them I not only saw all those places I had heard about but I made maps of them, made diagrams of all the homes in each town and city I visited. I took delight in putting into my records mention of real occupancy, genteel or disreputable. After four or five years of this work I knew a lot about our people, saints and sinners, rich and poor." 12

To ensure uniform standards of accuracy and presentation on its maps, the Sanborn Company published, in 1905, a Surveyors' Manual for the Exclusive Use and Guidance of Employees. A number of subsequent editions were published of this comprehensive and detailed instruction book. The introduction to the manual emphasized that "Sanborn maps are vastly different from all other publications, and the novice must start in with the idea that it is all new, though some former occupation, such as civil engineering and architectural work, should fit a man to readily grasp the primary principles. Our maps," the introduction explained, "are made for the purpose of showing at a glance the character of the fire insurance risks of all buildings. Our customers depend on the accuracy of our publications, and rely upon the information supplied, incurring large financial risks without making personal examinations of the properties." 13 The manual included more than a hundred pages of precise instructions and included sample maps and a comprehensive symbol key.

"The information reported," the Sanborn surveyor was advised, "is technical to the fire insurance world, and you should master the technicalities and ever bear in mind the use to which the map you are producing will be applied." 14

Maps were drawn at the scale of 50 feet to an inch, on sheets 21 by 25 inches, which were cross ruled in one-inch squares. The manual instructed surveyors to map all the builtup part of the town or city. "Information," they were told, "is generally available at the Court House, or . . . some real estate agent may have the necessary data. [However] if records are not easily obtainable do not waste too much time, but proceed to measure up the territory with tapeline, and plot sheets from notes so secured. In plotting put on the street names and widths and real estate description." 15

Each year Sanborn extended its coverage to additional cities and also issued revised editions and paste-on correction slips for previously published maps and atlases. Production probably reached a peak in the early 1930s. An article about the Sanborn Company published in the February 1937 issue of Fortune Magazine stated that "Sanborn maps describe the houses on every street in more than 13,000 U.S. towns and cities. . . [and] cost anywhere from $12 to $200 [per map] depending on the technical difficulties involved in making them up." 16

Sanborn maps were lithographically printed in the company's Pelham, New York, plant. With the aid of waxed paper stencils, Sanborn employees colored the maps by hand, because there were usually fewer than twenty orders for a single map sheet. They were issued as unbound sheets for towns and cities with maps of under a hundred sheets. Bound volumes, each with approximately one hundred plates, were published for large cities. Thirty-nine volumes were required for New York City. Around 1920 the company introduced a loose-leaf atlas format which made it possible to replace outdated plates without reprinting an entire volume.

By 1920 Sanborn virtually monopolized the insurance map industry. The company had only two or three relatively small competitors, including Walter I. Fisher who, operating in Minneapolis as the General Inspection Bureau, published insurance maps of more than 640 towns in Minnesota, North Dakota, and South Dakota between 1907 and 1930. Fisher survived as an independent mapper no doubt because of his policy "to map every town and every risk of any particular consequence unless the Sanborn people have already got a map, in that case we have to keep hands off because of the chances of treading on somebody's toes." 17

Sanborn early learned that having a monopoly in a very restricted and homogenous market invited critical observation and evaluation. Most of the company's customers were members of national or regional underwriting associations where they could discuss Sanborn's real or assumed deficiencies. One of the major concerns was the relatively high cost of Sanborn's products and services. The most active and persistent pressures on the Sanborn Company came from the National Board of Fire Underwriters which in 1914 appointed a special map committee to consider the possibility of sponsoring its own map publishing and distributing unit. During the next forty-five years NBFU's Map Committee worked closely with Sanborn with the objective of providing the fire insurance industry with the best possible maps at reasonable cost.18

The Sanborn Company weathered the various attempts by the National Board of Fire Underwriters to establish a competing map company for almost half a century, although it did submit to a measure of control and supervision by the NBFU Map Committee. Among other concessions, Sanborn added to its board of directors first one, and later two, members of the Map Committee.

The fortunes of the Sanborn Company did not depend, however, solely upon their relations with the NBFU and the fire insurance underwriters. Economic, political, and social conditions also influenced the sale of Sanborn maps and services. Thus, the construction boom in the middle and late twenties had an accelerating effect on fire insurance sales and upon the need for maps. During these years Sanborn prepared maps of a number of new towns and cities and resurveyed previously mapped areas. For particularly active construction areas, revisions of Sanborn maps were issued at six-month intervals.

The period of economic prosperity did not last and with the financial crisis of 1929 and the depression of the thirties, construction was curtailed, fire insurance sales lagged, and companies again exerted pressure on Sanborn to reduce the cost of its maps and services. Sanborn's response was to offer cash discounts to subscribers, offer the paste-on service for sheet maps (i.e., those for smaller towns and cities), and to mount the sheet maps on cloth to ensure longer life.

World War II placed restrictions on construction and on publication of maps. Sanborn, like most other map publishers, survived during these years by producing maps on contract for the military services. The hoped-for postwar prosperity was slow in arriving, particularly for the Sanborn Company. In an attempt to bolster declining sales, maps were published for a number of cities at the reduced scales of one inch to 100 feet and one inch to 200 feet (as compared with the standard one inch to 50 feet) and issued in small-size atlas format.

By 1960 it was evident that the fire insurance industry was undergoing major changes and the detailed maps and services offered by Sanborn were no longer required. In its 1961 report the National Bureau of Fire Underwriter's Map Committee noted that some companies had discontinued the use of maps and decided "to review the overall situation from the standpoint of the needs of business at the present time." 19

The following year the committee reported "there is a general (not unanimous) view that residential mapping is not considered essential by the companies or the bureaus, nor is it considered essential to have town maps for those communities which are predominantly residential, but that business and industrial areas for all other towns and cities warrant map service." 20 This was the final report of the NBFU Map Committee.

The report was actually more optimistic than Sanborn's business warranted. The market for Sanborn maps never recovered after World War II, and the last catalog issued by the company was published in 1950. In 1967 Sanborn's president, C. F. Doane, stated that "since 1961 there have been no new [catalog] entries [for insurance maps] for distribution. This company has limited itself to revision service for existing atlases and graphics prepared on a custom basis for non-insurance clientele." 21 The publications referred to by Doane are corrected, reduced-scale, photo-revision, black and white atlases for some 150 United States cities and towns that Sanborn has issued in spiral binding format since 1962. They update previously established data.

These atlases have not yet been deposited for copyright by the Sanborn Company. In 1977 S. Greeley Wells, president of the Sanborn Company, offered to present to the Library of Congress superseded volumes of Sanborn atlases in this series. Some forty-five volumes, covering urban areas in the states of Massachusetts, Connecticut, New York, and New Jersey have been received to date. The map legend, which is limited to black-and-white symbols, differs considerably from the legend for maps in the colored volumes. The scale employed for the spirally bound series is one inch to 100 feet, the same as in the small format atlases published after 1950.

In 1977 Sanborn copyrighted microfilm editions of fire insurance atlases for Chicago, Illinois, and Queens County, New York. The former includes nine reels and the latter four. The maps have been corrected to 1975. A microfilm edition of Washington, D.C. corrected to 1977, was copyrighted by Sanborn early in 1978.

The reasons why Sanborn maps are no longer widely used by the fire insurance industry are varied and complex, including a number of internal and external factors. The demise of insurance cartography did not occur suddenly and dramatically but was characterized instead by a slow and persistent decline over a long period of time. Because of the homogeneous nature of the clientele, new techniques, methods, and procedures developed in or introduced into one company were soon adopted by other members of the underwriting fraternity.

One such new method was the "line card" system for recording risks which was adopted by some companies as early as the mid-twenties. 22

Some companies, too, may perhaps be using computer storage for their liability and risk records. Even if they are not already, it is inevitable that such records will eventually be computerized.

Company mergers have also played a part in limiting the market for insurance maps. The resulting increased financial strength has enabled companies to maintain their own engineering departments to inspect and service questionable risks or to engage firms-such as the Sanborn Map Company-to make inspections and prepare maps on a custom basis.23

More specific reasons for the decline in use of Sanborn maps were supplied by a librarian for the Insurance Company of North America. "As the nation grew in all areas," she wrote, "keeping the maps up to date became cumbersome, time-consuming, and expensive. At the same time, increased financial strength of the Company and the progressive reduction in the number of instances in which we needed such detailed locality information led us to discontinue the service prior to 1950. No comparable source of data has replaced use of maps at INA. There is no need to maintain wealth of detail about the small risk to forestall the possibility of catastrophe from fire. Inspection services maintained by fire insurance rating organizations and our own inspection services have proved adequate in the light of modern building construction, better fire codes, and improved fire protection methods." 24

Although Sanborn maps today have minimal interest for the fire insurance industry, the Sanborn Company is supplying updated copies of many of its maps and atlases to various clients. Today municipal governments are Sanborn's best customers, accounting for 60 percent of map sales and services. Engineering and architectural concerns are also significant purchasers of corrected Sanborn maps.

A Sanborn official reports that of the company's basic records approximately one-third are large colored map sheets (i.e., one inch to fifty feet), another third are the small-format colored maps introduced in the 1950s, and the balance are reduced scale black-and-white photo offset maps. Paste-on correction services are still furnished for the New York and Chicago atlas series, based on survey checks of each building for updating. Correction sheets of other towns and cities, when requested, are supplied as black-and-white photoreproductions or as microimages in aperture cards. At its peak period of production before World War II, Sanborn employed seven hundred people, but the present staff numbers only forty-two with, however, some slow but steady growth.

The large file of noncurrent Sanborn maps and atlases constitutes an invaluable historical record of urban growth in the United States over more than a century. Local historians, genealogists and scholars consult the maps today for the wealth of detailed data which they embrace. The largest collection of Sanborn maps and atlases is preserved in the Geography and Map Division, Library of Congress, where there are an estimated 700,000 Sanborn maps in bound and unbound editions.

Many individuals have consulted the Library's Sanborn maps in recent years. Full use of this large and valuable collection will now be possible for a wider clientele through use of this volume and the inventory of LC holdings it provides.



  1. Hayward, Graham M. Personal letter dated October 19, 1973.
  2. Ibid.
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  3. Ibid.
  4. Excerpts from Jones's report, sent by Hayward as an attachment to his letter.
  5. Ibid.
  6. Ibid.
  7. Ibid.
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  8. See the exhibit catalog Maps for an Emerging Nation: Commercial Cartography in Nineteenth-century America, by Walter W. Ristow ( Washington: Library of Congress, 1977).
  9. Manufacturers Mutual Fire Insurance Company, The Factory Mutuals 1835-1935 (Providence, 1935), p. 59.
  10. "Sanborn Map Company" in Special Libraries Association, Geography and Map Division, Bulletin 27 (February 1957): 5.
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  11. Sanborn Map Company, Description and Utilization of the Sanborn Map (New York, 1953), p. 3.
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  12. Dan Beard, Hardly a Man Is Now Alive, the Autobiography of Dan Beard (New York, 1939), p. 225.
  13. Sanborn Map Company, Surveyors' Manual for the exclusive Use and Guidance of Employees of the Sanborn Map Company (New York, 1923), p. 4.
  14. Ibid., pp. 4-5.
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  15. Ibid., p. 9.
  16. "Map Monopoly," Fortune Magazine 15 (February 1937): 42.
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  17. John W. Gunn [President]. "Report," In Fire Underwriters Association of the Pacific, 33d Annual Meeting, Proceedings, January 5, 1909 (San Francisco), p. 19.
  18. Walter W. Ristow, "United States Fire Insurance and Underwriters Maps, 1852-1968." Quarterly Journal of the Library of Congress 25 (July 1968): 194-218. Reprinted in Surveying and Mapping 30 (March 1970): 19-41.
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  19. National Board of Fire Underwriters, 95th Annual Meeting, "Report of the Committee on Maps," in Proceedings, p. 132.
  20. Ibid., 96th Annual Meeting, 1962, p. 139.
  21. Letter dated February 24, 1967, from C. F. Doane, president, Sanborn Map Company.
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  22. Ristow, "United States Fire Insurance and Underwriters Maps," p. 38.
  23. Ibid., p. 40.
  24. Letter dated November 10, 1967, from Mrs. Adelaide S. Herman, Librarian, Insurance Company of North America, Philadelphia.
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  January 2, 2014
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