Fascinating early map of North America, issued immediately after the Louisiana Purchase in early 1803.
The most immediately noticable feature is the depiction of Louisiana as a massive political subdivision of the United States.
The western United States is largely blank, with the map pre-dating the major cartographic additions of the early 19th Century, including Humboldt's single cordillera (the Rocky Mountains), Lake Timpanagos and Lake Teguayo (the mythical Salt Lake), and the mythical rivers of the 1820s and 1830s. Interestingly, Teguayo appears as a place name in what would be the Arizona desert.
In the northwest, the supposed course of the Columbia River is perhaps the most interesting feature, depicted as turning due north and extending well into what would become British Columbia, likely confusing the course of the Frazier River. The coast of Alaska is known on a very limited basis. The Northwest Passage is clearly in evidence, with a wide Mer Selon Arrowsmith (Sea According to Arrowsmith) depicted.
The limited knowledge of the course of the Colorado and Gila Rivers is quite interesting, with a mountain range traversing Southern California in an east west arc blocking the path of the Colorado River. There is no sign of the Sierra Nevada mountains or the Coastal Range in California.
Nice detail along the NW Coast of America. Massive Louisiana Territory, but a decidedly pro-English treatment of what would become Oregon Territory.