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Subject: Plat maps
Date: Mon, 24 Nov 2003 11:27:33 EST
From: <[log in to unmask]>


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I work in a local history collection (District of Columbia) that
contains plat maps (e.g., published by Baist or Sanborn). These maps
were published approximately every 5-10 years for certain sections of
the city, and are one of the collection's most prized and frequently
used resources.

Occasionally, a patron will ask about the publishers' methodology: did
the surveyors collect information during the course of one year--the
year of publication--or were the data collected over a number of years?
For example, does the 1909 map reflect what was on the ground for 1909,
or might it show what was actually there in 1907?

Also, is there any consensus about the accuracy of one group of maps
over another? Are the Sanborn maps considered more accurate on the whole?

Any advice or information about these maps would be most appreciated.


Margaret Goodbody
Collections Librarian
Washingtoniana Division, Rm. 307
MLK Library
901 G Street, NW
Washington, D.C 20001