AMERICAN GEOLOGY — DECADE OF 1870-1879. 587 



November. In May, 1857, Hayden was again appointed geologist by 

 Lieutenant Warren, this time on an expedition to the 



Hayden with .... . . 



warren in the Black Black Hills. I he party was organized at Noux City 



Hills, 1857. . r , ii ii T t^ , » , 



in f J une and proceeded up the .Loup i'ork or the 

 Platte, returning to Fort Leavenworth, Kansas, early in the following 

 December. 



Hayden noted the occurrence of — 



1. Metamorphic Azoic rocks, including granite. 



2. Lower Silurian (Potsdam). 



3. Devonian (?). 



4. Carboniferous. 



5. Permian. 



6. Jurassic. 



7. Cretaceous. 



8. Tertiary. 



9. Post-Tertiary and Quaternary. 



In a preliminary report given by Warren in the American Journal 

 of Science for Ma} T , 1859, attention was called to the important physi- 

 ographic fact that the Niobrara River seemed kt to run along a swell or 

 ridge on the surface and to be practically without tributaries." 



This would seem to be a recognition of the fact, though not the prin- 

 ciple, that streams flowing from a mountainous country and laden with 

 silt may, in their lower levels where the current is less rapid and the 

 carrying power less, so deposit their load as to build up both the bot- 

 tom and banks, and this until the stream actually occupies the crest of 

 a ridge. The Platte River is, however, a better illustration of this 

 than is the Niobrara. That portion of the channel running between 

 steep bluffs he thought ''must have originated in a fissure in the rocks 

 which the water basins enlarged and made more uniform in size." 

 This failure at this late day to realize that a stream may carve out its 

 own channel can be excused only on the ground that Warren was not 

 a geologist. 



During the summer of 1858 Messrs. Hayden and Meek explored a 



portion of what was then called the Territory of Kansas. The route 



followed, as given by Hayden in his report published in the Proceedings 



of the Academy of Natural Sciences of Philadelphia, 



Ka e nsa a s n ,8 H 5 a 8 3 : denin ™S as follows:' 



From Leavenworth City on the Missouri, across the 

 country to Indian ola near the mouth of Soldier -Creek and the Kan- 

 sas River; thence up the north side of Kansas and Smoky Hill rivers 

 to the mouth of Solomons Fork. Here they crossed the Smoky 

 Hill, following it up on the south side to a point near the ninety- 

 eighth degree of west longitude, from which point they struck across 

 the country in a southwest direction to the Santa Fe road, which 

 was followed northeastward to the head of Cottonwood Creek. 



