Railroad map of Michigan / prepared for the Commissioner of Railroads by O.W. Gray & Son.O.W. Gray & Son1876"Entered according to act of Congress in the year 1874 by G.W. & C.B. Colton & Co. ..."Appears in Michigan Railroad Commission. Fourth annual report. 1876, and in McCracken, S.B. The state of Michigan. Lansing, 1876.Includes inset of "part of Michigan"cartographic