This is the 1855 issue of J. H. Colton’s map of Illinois.  Depicts the state of Illinois along with parts of neighboring Iowa, Missouri, Indiana and Kentucky.   Color coded according to county.  Shows major roadways and railroads as well as geological features such as lakes and rivers.   An inset in the lower left quadrant focuses on the vicinity of Chicago.  Dated and copyrighted: “Entered according to the Act of Congress in the Year of 1855 by J. H. Colton &amp; Co. in the Clerk’s Office of the District Court of the United States for the Southern District of New York.”  Published from Colton’s 172 William Street office in New York City, NY.
<bdi><a href="https://en.wikipedia.org/wiki/en:J._H._Colton" class="extiw" title="w:en:J. H. Colton"><span title="United-States geographer and mapmaker">J. H. Colton</span></a>
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1855 (dated)
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