GEOLOGICAL SURVEY OF THE TERRITORIES. 145 



Altliougb the spriug and basin are very cbaste and delicate in form as well as color, 

 tbere are otber springs more beautiful in tbose respects. But when I ascended the 

 bank and looked down upon the spring and its surroundings, I concluded, without the 

 least hesitation, that I bad never seen anything so uniquely beautiful. On the up^jer 

 side of the spring, next to the bank, the water in overfiowiug ran into large shallow 

 pools, painthig whatever it touched with the colors of the rainbow. Beds of rich, creamy 

 white and rich yellows were interlaid with patches of siennas and purples, and di- 

 vided up and surrounded by the most fantastic patterns of delicate grays and rich 

 browns. On the side nest the creek the running water has made a net-work of streams. 

 In those where the water is still hot, the colors are bright, varying from a creamy 

 white to the brightest yellows, but, as the water becomes cooler, farther down, the 

 colors grow darker and richer, the siennas greatly predominating, while the basins 

 of the larger jjools are stained with still darker colors, frequently of a purple tint and 

 reflecting the picturesque groups of pines on their dark surfaces. Scattered' irregularly 

 over the whole surface are numberless little areas of dry deposit, from which the 

 brighter tints have faded but which still retain such a great variety of purple and 

 bine grays that the harmony of the whole field of color is complete. 



Mr. Holmes, in his description of the Great Fountain, refers to the 

 pebbles of geyserite in the pocket-like depressions surrounding it. 

 These pebbles vary in size from that of a pea to two or three inches in 

 diameter. They are made up of concentric layers. The following an- 

 alysis which I have made will give their composition : 



Analysis. 



Per cent. 



Loss at 100° C ' 3.75 



Loss on ignition 5.25 



Silica 88.60 



Alumina and iron 1. 60 



Lime 0.95 



Magnesia Trace. 



Soda* Trace. 



Potash* Trace. 



Lithia* Trace. 



100. 15 



Farther up the ravine, at the mouth of which this geyser is situated, 

 is a group of springs around which the deposit, instead of being white, 

 as in the case of other springs, is black. These springs were referred to 

 in the report of 1871, page 184. 1 have made an analysis of this de- 

 posit and find it to consist as follows : 



Analysis. 



Per cent. 



Loss at 110° C 2.66 



Loss on ignition , 6. 33 



Silica ^. 82.80 



Alumina 5.64 



Iron 1.49 



Lime 2.13 



Magnesia Trace. 



Soda* Trace. 



Potash* Trace. 



Manganese* Trace. 



101. 05 



The color of the specimen I believe to be due to the large amount of 

 organic matter included in the above analysis under the loss by igni- 

 tion. 



There was one quite large group of springs in the lower basin, during 

 the summer, which escaped our notice during the season of 1871. For a 



* By spectroscopic examination. 

 10 G S 



