Father De Smet did a great deal of work in the line of map-making. He thus refers to this matter in one of his letters: "During the ten years I spent in the Indian country I occupied myself occasionally in drawing maps of the countries through which I passed. I availed myself of the best information I could obtain from trappers and intelligent Indians who were well acquainted with the mountain passes and the course of the rivers. Not having had instruments with me, the maps were necessarily only an approximation to the true positions." Before his death he gathered together into an ordinary stub-file all his manuscript maps. They are not executed with a degree of technical skill in draftsmanship to justify their reproduction; but they are extremely interesting and valuable historically. We may cite, as a single instance, that, although the Yellowstone Park country was not made known to the world until 1870, these maps, prepared before 1850, show nearly every feature of interest in that wonderful region.(1) In 185I Father De Smet, at the request of D. D. Mitchell, drew a map of the western country for the Government, and it is now presumably on file in the Bureau of Indian Affairs in Washington.
The writings of Father De Smet are full of references to the fauna and flora of the country. There is not much original matter in these descriptions, and the changes in scientific nomenclature since they were written are so great that it is hardly worth while to attempt to utilize them. In a general way, however, there is a great deal of interest in his notes on the larger animals, such as the buffalo, beaver and bear, and the large space that these animals filled in the life of the Indian and of the early pioneers.
The fund of Indian lore contained in the Letters has permanent value. It includes descriptions of the manners and customs of the Indians, their traditions and notable
(1) See pages 182 and 661 of the Letters.