PEALE.] SPRINGS OF YELLOWSTONE LAKE, 117 



These springs at present, therefore, represent the last stages of ther- 

 mal activity, and were once probably connected in some way with the 

 Sulphur Hill Springs. 



LAKE BUTTE SPRINGrS. 



ISTorth of Lake Butte, between it and the mouth of Turbid Creek, but 

 nearer the former than the latter, is a small group of hot springs and 

 steam jets. They are near the shore, on the east side of the beautiful 

 bay* that lies east and south of Steamboat Point. There are four or 

 five principal springs on the slope of a bluff or hill that is bare of vege- 

 tation, and covered with a reddish deposit, on which there is, in a few 

 places, a deposit of alum. The highest temperature observed was 1 92° 

 F., and the lowest 110° F. Below these about a quarter of a mile are a 

 few iron springs, on the side of the butte near the base. The average 

 temperature here was about 170°. Common salt was observed in some 

 of the springs, but sulphur, silica, and iron appeared to be the principal 

 deposits of this group, which is comparatively unimi^ortant. No con- 

 nection with the springs of Steamboat Point, which is so near, nor with 

 the Turbid Lake Group could be determined. 



BRIMSTONE BASIN. 



This name has been given to a basin of spring deposits, which are 

 on the northwestern slopes of the ridge that extends southwest from 

 Mount Stevenson. It is about a mile east of the lake, and covers an 

 area of about 3 miles in extent. It is easily seen from a distance, the 

 white deposit on the slopes rendering it quite conspicuous, and the 

 sulphurous odors greet the visitor some time before he reaches the 

 place. At present there are no warm springs at this locality, although 

 there are mauy places in the channel of the small creek which bubble 

 with sulphureted hydrogen. The deposit is generally white, mingled 

 with yellow and blue clay. Sulphur is abundant, and it is the source 

 of the sulphureted hydrogen. The stream draining this basin is 

 strongly im]->regnated with alum, and has been called Alum Creek. 

 Its channel is coated with sulphur, and the water is milky in its hue. 

 ]^ot even the trace of a spring with a temjierature above that of ordi- 

 nary water could be found, although the deposits give evidence that 

 some time in the past this was the seat of very active thermal springs. 



COLD SPRINGS AT HEAD OF PINE CREEK. 



While the cold springs of Brimstone Basin are described, it may be 

 interesting to mention the springs at the head of Pine Creek, described 

 as follows byDr. Heizmann : 



11 



by little, round holes, from whicli bubbles of {;iis ascended at intervals of one minute 

 exactly. It showed no reaction of any kind, wbilo the gas collected was suspected 

 to be sulphurous-acid gas, on account of its bleaching litmus paper. Tests for car- 

 bonic acid and sulphureted hydrogen were frequently but fruitlessly applied. These 

 springs were remarkable because of being sui generis, none analogous having been 

 found afterward in the other liills or valleys of this region. t 



This locality may represent a stage of decay many steps in advance 

 of Brimstone Basiu. 



*This is the bay that was originally named Mary's Bay, but on the map the name has 

 been given to the bay north of the ])oint. 

 t Report of Reconnaissance of N. W. Wyoming, by Capt. W. A. Jones, 1873, p. 296. 



