PEALE.] GIBBON EIVER SPRINGS. 133 



following description is from Mr. IS'orris. He says the group is spread, 

 over somewhat less than 5 acres, and contains numerous hot springs, 

 among which are twelve geyser cones from 2 to 20 or 30 feet in height, 

 in form similar to the Liberty Cap of Gardiner's River, The majority 

 are in a dead or dying condition. One has its orifice horizontal in the 

 summit of the cone. There is at least one powerful geyser in the group, 

 and whenever there is water from an eruption it pours down the slope 

 of the spur in a series of cascades. 



About 2 miles down the cauoh is another small group in which there 

 is a geyser which we call " Oblique," that spouts out obliquely over the 

 road. 



LOWER GROUP ON GIBBON'S FORK. 



This group is situated about half a mile above the junction of Gibbon's 

 Fork with the Fire Hole Ei ver. The springs were first visited probably by 

 General Gibbon, who partially explored the stream which now bears his 

 name. He directed Professor Bradley to the springs, who describes 

 them in his report for 1872.* Still later Dr. Hayden and myself visited 

 them, t and the description I shall give will be compiled from these 

 reports. 



The springs are on the north side or right bank of the river in a valley, 

 about a mile in length and a half mile in width. These are on a ter- 

 race at the base of the hills back from the river, above which their ele- 

 vation is from 80 to 100 feet, the deposit covering several acres. The 

 water flows from a dozen or more different openings. The largest spring 

 is in reality a small lake or reservoir, at one end of which are two orifices, 

 one of which is constantly boiling. 



It is of an irregular form, something like the outline of a goat-skin bottle, with the 

 spring in the mouth of it, about 200 feet long by from 50 to 90 feet wide in its main 

 part, while the narrowest part of the neck is from 10 to 15 feet wide. 



The temperature I obtained in 1872 was 140°. Professor Bradley de- 

 scribes the temperature as follows: 



The temperature at the point of nearest safe approach to the center of ebullition 

 was 146°; 100 feet distant, the water escaping from the pool gave 126°; while the 

 farthest jioiut of the pool gave 120°. The eyjt flow was rapid, along a channel aver- 

 aging about 3 feet wide by 9 inches deep. This had built up its banks a few inches 

 above the surrounding level, and at two or three points the deposit had even bridged 

 the stream. 



The spring at the end of this pool is a pit from 2 to 3 feet in diameter 

 and about 15 feet in depth. In this, which is constantly boiling, the 

 water is projected 1 to 3 feet into the air, above the surface of the pool. 

 Two small streams flow into this lake like pool, having their origin in 

 two springs that have temperatures of 135° F. to 150° F. One of them 

 is a pulsating spring, and the water spouts about a foot. A short dis- 

 tance east of the pool are two springs with temperatures of 100° F. and 

 1220 F. 



A second pool, quadrangular in form, measuring 50 feet on a side, is 

 described by Professor Bradley. The center of ebullition could not be 

 approached, and the temperature along the edges of the pool was only 

 1130. 



The smaller flows varied from 110° up to iri4°, and in one case up to 150°. Several 

 old openings along the outer edge of the terrace were long since deserted, and the flow 

 is now only from higher levels farther back. The deposit thus appears to stop up the 

 channels and so to force the water back until it finds or makes now openings in the 



^ Report U. S. Geol. Survey of the Terr, for 1872, 1873, p. 230. 

 ilbid., pp. 55 and 159. 



