GEOLOGICAL SURVEY OF THE TERRITORIES. 



125 



Dr. Endlicli lias lujule the following analysis of the deposits from these 

 springs : 



Per cent 



Loss at 110° C 1. 75 percent. / 32 10 



Loss at ignition . . 30. 35 per cent. ^ 



Lime 57. 70 



Silica 3.32 



Ferric oxyd 3. (52 



Alumina 3.31 



Magnesia Trace. 



Soda* Trace. 



100. 05 



Fig. 32. 



Figures 31 and 32, drawn by Mr. Holmes, will perhaps give the reader 

 a good idea of some of the peculiar formations noticed at these springs. 

 Fig. 31 shows the pools or basins which were so fully described by Dr. 

 Hayden in the report for 1871, and which form one of the most beautiful 

 features of the springs. The 

 water in all of them is either 

 warm or hot according to their 

 position, the lower ones having 

 the coolest water. The water 

 has also that exquisitely beau- 

 tiful blue tint which is beyond 

 description, and which forms 

 such handsome contrasts to 

 the white, marble-like basins 

 in which it is. The water pours 

 from one basin to another and 

 forms stalactitic processes, 

 which hang from their sides 

 as seen in the picture. At the 

 bottom of the upper basin in 

 the illustration the processes 

 have united with those formed ornamental rim of extinct spring, gardim^rs river. 



from below by the dropping of the water, while in the lower basin they 

 have not yet come together, but still form true stalactitic processes. Over 

 the outside surfaces of the basins we find also bead-like processes, caused 

 also by the drop})ing of the water. The great amount of lime in these 

 deijosits gives them a beautiful wliite appearance. 



CHAPTER III. 



GAEDIKER'S EIVER TO MUD VOLCANOES, YELLOWSTONE 



VALLEY. 



We left the Hot Springs on the 29th of July and made our next camp 

 on Black-Tail Deer Creek near the Yellowstone, a few miles above Gar- 

 diner's River. Our camp was on a portion of the plateau that extends 

 eastward from the top of the bluft-wall opposite the springs. The rock 

 immediately beneath us was a violet-colored trachyte containing crys- 

 tals of sanidine. Between our camp and the Yellowstone River there 

 were some exposures of Carboniferous limestone, evidently the direct 



"Bj spectroscopic examination. 



