6 GEOLOGY OF THE BLACK HILLS. 



region south of the Pacific Railway, partly because of the hostile Indians, 

 the expense of transporting supplies, and the barrenness of the country, 

 but especially because the more rapid settlement of the south has demanded 

 the prior exploration and opening up of that part of the Plains. To illus- 

 trate the progress of exploration in the Upper Missouri Region, and par- 

 ticularly to show the course of exploration in the area of our last summer's 

 work, the different expeditions that have passed over and examined this 

 northwest territory will be briefly reviewed. Many of the facts relating to 

 the earlier expeditions are derived from Dr. Hayden's paper in the report 

 of General W. F. Raynolds' "Exploration of the Yellowstone and Missouri 

 Rivers" (1859-1860). 



The first authorized expedition made by our government, and the first 

 intelligent exploration of the Upper Missouri region was conducted in 1804, 

 '05, and '06, by Captains Lewis and Clarke of the United States Arm}^, who 

 were commissioned in 1803 by President Jefferson They started in the 

 spring of 1804, following up the Missouri River to its source, and then push- 

 ed across the Rocky Mountains to the Columbia River and the Pacific. Re- 

 turning, they descended the Yellowstone to the Missouri and the Missouri to 

 Saint Louis. Their journal, published in 1814,* contains the first reliable 

 account of this great northwest territory, and though of exceeding interest, 

 especially in relation to the Indian tribes they encountered, it contains little 

 or no information as to the geological structure of the country. They col- 

 lected a few fossils, however, and from their study Dr. Mortonf was able to 

 establish the presence of the Cretaceous formation on the Upper Missouri. 



A long period intervened before the next expedition of note, which 

 was made in 1832, by Prince Maximilian of Neuwied, who ascended to the 

 headwaters of the Missouri. The results of his travels were published in a 

 most elegant manner, profusely illustrated from sketches made in the field, 

 which possess much artistic value, beside being truthful pictures of the 

 country and natives. Maximilian noted more carefully than his predeces- 



* History of the expedition under the command of Captains Lewis and Clarke to the sources of the 

 Missouri, theuce across the Rocky Mountains and down the river Columbia, &c, during the years 1804, 

 '05 '06, by order of the United States Government. 2 vols, 8vo. Philadelphia, Bradford and Inskeep, 

 1514. 



t Synopsis of the Organic Remains of the Cretaceous Groups of the United States, etc. By S. G. 

 Morton. Philadelphia, 1834. 



