Map of the battle field of Gettysburg, July 1st, 2nd, 3rd 1863. First day battle. Published by authority of the Hon. the Secretary of War, Office of the Chief of Engineers U.S. Army. 1876. Positions of troops compiled and added for the government by John B. Bachelder. Topography engraved by Julius Bien, 16 Park Place N. Y. Position &amp; lettering by Louis E. Newman, 36 Vesey St., N.Y. Printed by Endicott &amp; Co., New York.<br> 
Third map of the battle field of Gettysburg, July 3rd, 1963. Relief shown by contours, form lines and spot heights. Scale:1:12,000. 1 in. represents 1000 ft. Shows Gettysburg environs, place names, the posi+tion of the troops by color and signal stations Includes notes. "The survey was ordered by Brevet Major General A.A. Humphreys, Chief of Engineers, and conducted under Brevet Major General G.K. Warren, Major of Engineers."
Bachelder, John Badger, 1825-1894
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