1. Map Of An Exploring Expedition To The Rocky Mountains in the Year 1842, Oregon & North California In The Years 1843-44. By Brevet Capt. J. C. Fremont Of The Corps Of Topographical Engineers Under the orders of Col. J.J. Abert, Chief Of The Topographical Bureau. Lith. by E. Weber & Co. Baltimore, Md (Raster Image) Datasets Stanford University Public content 1842, 1843, and 1844. Rumsey, David, 1944- and Southern Pacific Company. The large map of the west is one of the most interesting and beautiful government maps of the 1840's. It filled in many of the gaps in cartographic... Cartography Associates.