Rare early 1851 edition of Mitchell's map of the West, one of two post 1849 editions which predates the formation of Washington Territory.
While the title is the same as the 1850 edition, this is in fact the first edition of the map to be issued on the new plate, which shifts the land mass westward, showing less of the Pacific and more of the Rocky Mountains. Oregon extends to Missouri Territory and the Rocky Mountains.
In this edition, no counties are shown. Counties would be shown in the second 1851 state of the map.
The Bartlett and Graham Line's are shown, pre-dating the Gadsden purchase. Kearney's Route is shown, as is the Spanish Trail from Santa Fe to Los Angeles. The Oregon Route is also shown, as is Fremont's route and Cook's Wagon Route. Many early forts and Indian tribes appear. The boundary of 1819 with Spain is also shown, pre-dating California's annexation into the US. Massive Tule Lake and no sign of Lake Tahoe.
The two 1851 editions of the map are easily distinguished. The first edition of the map has no counties in Oregon, Utah and New Mexico, whereas this, the second edition of the 1851 map, has counties along the coast of Oregon and throughout Utah Territory and New Mexico. This map is technically the last of the 1846-1849 series, which extends only to the Rocky Mountains. In the second edition of 1851, the map is completely re-engraved, with the new plate extending further east of the Rocky Mountains, to incorporate most of Colorado (then still Indian Territory).