134 GEOLOGICAL SURVEY OF THE TEERITOEIES. 



aggregate height of which is 120 feet. The stream , after passing throngli 

 a deep, gloomy gorge, makes a leap of about 21 feet and then falls again 

 in three streams a distance of over 50 feet into a beautiful, ronnded 

 basin, in which the water is perfectly clear and qliiet. From this basin 

 the final leap is taken and the water flows on to the Yellowstone Kiver. 



Leaving Cascade Creek our next camp (Xo. 13) was at Alud Volca- 

 noes near the Yellowstone Eiver, about eight miles below the lake. We 

 spent three days here, waiting for a supply-train to join us from Fort 

 Ellis. During this time I visited a number of the various hot-spring 

 localities in this portion of the valle3\ The underlying rocks here are 

 Pliocene and Post-pliocene, in horizontal strata, and presenting the same 

 characters that were observed near the Grand Canon, and i)robably 

 resting, as those do, upou volcanic rocks. In some places 1 noticed iron 

 as forming a prominent part of these sedimentary deposits, which, with 

 the obsidian, makes very handsome sj^ecimeus. The river flows quietly 

 through the valley, the fall per mile, from Yellowstone Lake to the top 

 of the upper fall, being oidy 8 feet, and almost all of this is in the rapids 

 jiisr above the upper fall. The first springs I visited were on a branch 

 of Alum Creek about five miles northwest of camp. We named the small 

 stream Violet Creek, from the profusion of violets growing upou its 

 banks. 



The first spring we met with was on the right bank of tlie creek, in a 

 siliceous cone like uuDund that rises six feet above the bed of the stream. 

 Its temperature was 120° F., the air being at 70° F. The bed of the creek 

 was filled with confervoidea, leading usto suspect that there were springs 

 still farther up. After a further ride of about a quarter of a mile we 

 came to quite alarge group of hot springs lining both sides of the creek. 

 The first spring I will describe is on the right bank of the creek, in the 

 center of a white mound 20 feet in diameter and rising 10 feet above the 

 bed of the creek. This mound is formed of the deposits from the water, 

 which consist mainly of various carbonates and silica. The orifice of 

 the spring is circular and about three inches in diameter and looks as 

 though it had been artificially punched in the deposit, so njathematically 

 exact is it. The water gives off carbonic-acid gas, leaving a deposit of 

 iron. Its temperature was 190° F., the air being 70° F. Spiing Xo. 2 

 is on the opposite side of the creek and has a basin measuring 4 feet by 

 2 feet; the temperature of the water was 1(50° F., the air remaining at 

 70*^ F. Xo. 3 has a circular basin two feet in diameter, which is lined 

 with an abundant deposit of iron. Carbonic-acid gas bubbles through 

 the water. Its tem])erature was 158° F. Xo. 4 is G feet deep and 1 

 foot by 3 feet in diameter, and has a temperature of 188° F, The 

 next three springs Ij^ad temperatures as follows: Xo. 5, 192° F.; Xo. 6, 

 104° F.; and Xo. 7, 188° F.; the air still remaining at 70° F. All these 

 springs have circular orifices of about six inches diameter, aud the water 

 proceeding from them flows over a series of small terraces, resembling 

 those of the Gardiner's Eiver springs on a miniature scale. These basins 

 are lined with a gelatinous form of silica, which has a leathery appear- 

 ance and is coated with an iron deposit. The springs are about 10 feet 

 above the level of the creek and all give off carbouic-acid gas. Xo. 8 

 is very irregular in shape and almost hid in the grass, about 40 feet from 

 the creek. There is a slight bubbling in it and its temi)erature was 

 178° F. Xo. 9 is a small spring, 2 feet in diameter and 1 loot deep, 

 liued with confervoidea and having a temperature of 140° F. Xo. 10 

 is a very pretty spring, about four feet above the creek, and has a beau- 

 tiful scalIoj)ed edge, moss-lined on one side. Its temperature was 175° 

 F. The boiling-point at this locality is 198°.3 F. Xoue of the spring's 



