742 BULLETIN UNITED STATES GEOLOGICAL SURVEY. 



In a recent number of the Naturalist, a list of tbermometric experi- 

 ments is given of a number of springs in the vicinity of Silver Peak, 

 by a gentleman* who visited the locality at the same time my observa- 

 tions were made. These springs are located chiefly in the western bor- 

 der of a large salt marsh. They run irregularly north and south, and 

 pone of them are of large extent, ranging from several feet to a few 

 yards in diameter. 



The first of these springs was originally of larger size than it is now; 

 owing to a long-continued deposit of saline matter around the border, 

 a crust was formed, which has gradually narrowed the opening to a 

 diameter of not more than five feet. How far the water recedes under 

 this formation is not known. The chief constituents of the water are 

 borax and several compounds of soda. It is also strongly impregnated 

 with and emits sulphureted hydrogen gas, 



No. 2 is also rather saline and unfit for use. It is situated about 

 twenty yards from No. 1, and measures about 18 feet in diameter. 



Observations taken July 7, 1871. 



6.30 a. m. 7.35 a. m. 

 i Dr ' " 

 I Wi 



.Dry hum 62.4° 73 



Air 



Temperature of .. ^ I Wet hull) — 70.8° 



I Water 67.5° 69.0° 



No. 3 is also saline and nearly closed over with incrustations. 



Temperature 79° 



No. 4, four feet distant from the last named, and about one hundred 

 paces from No. 2. 



Temperature 117° 



No. 5, about ten or twelve paces from No. Q, very strongly impreg- 

 nated with sodium chlorid. 



Temperature I 116.5° 



No. 6, saline; the examination was made late in the day, which ac- 

 counts for the difference in the temperature of the air, as given below. 



Temiierature of water 79.0° 



Temperature of air 6G.u° 



No. 7 was the last upon which I took notes, and was also the most 

 northern visited by me. Frequently emitted steam. 



Temperature of water 117.8° 



Lieutenant Lyle mentions several others, chiefly saline, of which the 

 temperatures were respectively 79°, 117.8°, and 116.5°. I am inclined 

 to believe that the last named is No. 5 of my list. 



About forty miles east of Silver Peak and six or seven miles north- 

 northeast of Montezuma we encamped near several springs located at 

 the base of Mount Nagle, or rather the northern spur of the mountain. 

 No. 1 contained scarcely any saline matter, but was strongly impreg- 

 nated, and emitted a great deal of sulphureted hydrogen gas. 



* D. A. Lyle, U. S. Army. <Am. Nat. vol. xii, No. 1, 1878, pp. 18-27. (1. c.) 



