William Darby was for many years a surveyor in Louisiana and it is for this and Texas for which this book is justly well known. Wagner-Camp states “Although written with an emphasis on the more settled regions of the Ohio and Mississippi valleys, this guide contains data about the trans-Mississippi country, based only in part on previous accounts. Darby was for years a surveyor in Louisiana; his geographical interest and personal knowledge from various explorations in Texas, Louisiana, and along the Canadian border gave him a voice in the delineation of the boundaries of the united States in both areas”. The large folding map at the beginning so often missing from examples features the United States but extends westwards to the Rocky Mountains. It includes all of Texas where a legend placed states “This part of the Provincias Internas, is but imperfectly known; no scientific traveller having ever explored, the wide range from St. Antonio de Behar to Red River”. The outline of Texas is coloured to extend to the headwaters of the Rio Grande and the Red River. There is also a single page township diagram and a fold-out map of Mobile, Perdido, and Pensacola Bays. Provenance: George Ritzlin, Chicago 2000; Burden Collection. Howes D61; Sabin 19527; Wagner-Camp 14b; Wheat ‘Transmississippi West’ 326.