Transcribed from the original: 'Made in 1851 under the direction of Col J.J. Abert, Chief of Corps Topographical Engineers, by BVT. Capt. L. Sitgreaves, T.E., assisted by Lieut. J.G. Parke, T.E., and Mr. M.H. Kern. Drawn by R.H. Kern, 1852.' 'Gila River from a reconnaissance by Maj. Emory, Topographical Engrs. Colorado River below Camp Yuma from a reconnaissance by Lt. Derby Topographical Engrs.' Shows Indian villages and forts. Upper right corner partially missing. Scale [ca. 1:650,000]. Scale of 10 miles to one inch.' 'Ackerman Lith.: 379 Broadway, N.Y.'