[Prepared to accompany the report of Capt. A. A. Humphreys and Lieut H. L. Abbot, Corps. of Top'l. Engrs., U.S.A. to the Bureau of Topl. Engrs., War Dept. Drawn by Chs. Mahon] Mahon, Charles. . CREATED/PUBLISHED Phil. Bowen & Co. lith. [1861] NOTES Scale