Map of the territory of Montana with portions of the adjoining territories / compiled and drawn by W.W. De Lacy, civil engineer & surveyor, Helena, M.T.De Lacy, W. W. (Walter Washington), 1819-18921878"Entered according to act of Congress in the year 1870 by W.W. DeLacy in the office of the Librarian of Congress at Washington."Includes inset of northwestern portion of the United States.Prime meridians: Greenwich and Washington.Relief shown by hachures.cartographic