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Historic Topographic Maps
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The United States Geological Survey was established on
March 3, 1879 and
began its topographic atlas of the United States in 1882. The oldest
map in this online collection dates from 1885 and covers part of
Washington, D.C. This online collection of over 2000 USGS topographic
maps includes complete geographical coverage of New England, New York,
Pennsylvania, New Jersey, Delaware and Maryland from the 1890s to
1950s. It is slowly being expanded as time permits, through volunteer
efforts. Most of the states of Virginia, West Virginia and Ohio are
now covered.
Current USGS topographic maps are available in paper form from the USGS, through
customized prints from MyTopo.com, via
map software such as Terrain Navigator,
and on the Internet with free services such as MyTopo's
MapServer.
While current USGS topographic maps are also often available in larger
public libraries, historic maps are usually more difficult to find,
which is why this web site was created.
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U.S. Geological Survey maps are published in increments of longitude and latitude. In the 15-minute map series, each individual map covers a rectangular area of 15 minutes. (For example, the Concord, New Hampshire quadrangle has a southern boundary of 43 degrees 0 minutes and a northern boundary of 43 degrees 15 minutes.) Other map series include 7.5- and 30-minute quadrangles, each drawn at different map scales.
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The USGS assigns each quadrangle a name, based on a prominent town, city or geographic feature (for example, a large mountain). However, the entirety of the title feature may not be completely displayed within the map of that name. This may cause occasional confusion. For example, in the 15-minute map series for New Hampshire, there is no quadrangle called "Nashua". The city of Nashua occupies parts of four quadrangles (including one named for Groton, a town in Massachusetts).
Not only are the names often unexpected, they are only unique within that state map series. For example, there are "Salem" quadrangles in both the 7.5 minute and 15 minute Massachusetts series. Both Vermont and Massachusetts have a 15-minute quadrangle titled "Barre." In addition, the names of some quadrangles were changed when new editions were created. The first edition covering the seacoast and border area of Massachusetts and New Hampshire was named "Newburyport," while later editions are called "Exeter."
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Edition, Survey, and Revision Dates
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Nearly all of the maps have an "edition" date and one or more survey and revision dates. For more recent maps, the type of survey (aerial photographs, etc.) is also listed. Use the survey and revision dates to determine the vintage of the cartography. These dates are usually found in a map's lower left corner.
Edition dates (in the lower right corner) can be confusing, because over time, the USGS has changed the method by which Edition dates are assigned. For the earliest maps in the 1890s, new edition dates were assigned nearly every time the map was reprinted. (This Historic USGS Collection does not include samples from each such printing, instead relying on the survey dates to distinguish between maps.) In later years, the original Edition date was retained for each subsequent reprinting. Such dates may be assumed to roughly represent the year that the map was first published.
Some maps also note a "reprinted" date. It appears that sometime around 1951, the policy for edition dates was changed again, and for reprintings made since, the Edition date has been based on the date of the last survey. This can lead to some confusion when comparing maps of the same title, but different edition dates. For example, this collection contains two Fryeburg, Maine 15-minute quadrangles, with edition dates of 1909 and 1911. The 1909 map contains a small line with the date 1964. The two maps are otherwise the same, the "1909" map actually being a reprint made much later.
7.5-Minute Series Maps, Scale 1:31,680
With the exception of a few areas of Vermont, all the 7.5-minute series maps in the collection depict southern New England and scattered sections directly outside the New England border. These titles were first published in the late 1930s, and used a scale of 1:31,680 until the early 1950s. In the 1950s, two new scales were adopted: 1:24,000 and 1:25,000. Coverage at this scale was not provided for New England until the 1960s,
Since the early 1950s, the 7.5-minute series has been published at scales of 1:24,000 and 1:25,000. The 1:24,000/25,000 series of maps was not published for northern New England (Vermont, New Hampshire, and Maine) until the 1960s, and consequently these maps are not included here, as this collection focuses on earlier historical coverage. However, complete coverage of Connecticut, Massachusetts, and Rhode Island is available at this scale. (Since surveying efforts did not extend north of the Massachusetts border at the time of these printings, areas north of this border were left blank.)
15-Minute Series Maps, Scale 1:62,500
This series provides complete coverage of New England and most of the rest of the northeast, although the range of dates is much more restricted in southern New England and in parts of Maine. This series includes the first USGS maps of New England, with southern coverage completed around 1900. The oldest coverage for Vermont and New Hampshire dates to the 1920s, while parts of Maine were not mapped until much later. The USGS stopped revising the 15-minute coverage for southern New England (Massachusetts, Connecticut and Rhode Island) around 1920, so for these areas, this collection contains no coverage more recent (except along the border with northern New England).
This lack of revision south of the Massachusetts border becomes readily apparent in some cases. For example, the Groton, Massachusetts 1935 quadrangle contains no indication of the rail line that was built after the original edition was surveyed. The rail line is shown in New Hampshire but does not appear south of the border, even though the line continued south to Ayer, Massachusetts.
30-Minute Series Maps, Scale 1:125,000
Existence of these maps varies from one area of the country to another. This collection's six titles, covering parts of Connecticut and Massachusetts, were created from the surveys for the 15-minute series maps that were done before 1900. In other parts of the country (Arizona, for example) this is the most common scale for older USGS maps.
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The Images and Access to Them
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Each state featured in this collection includes an image map showing a grid marked off in 15-minute increments. Each grid rectangle links to a web page that lists the coverage available for that quadrangle. In addition, there are alphabetic listings by quadrangle name and by town name for each state. There are usually four images corresponding to each date available, because the maps were usually scanned in four sections. Each image is typically 1.5 megabytes and is presented as a raw .JPG image. This file size was selected in order to maintain an acceptable level of detail.
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