1878. | ` The Springs of Southern Nevada. 21 
advance was carefully tested by striking the tufa with a mining 
hammer, to see if it would bear the weight of a man. Thus, by 
slow degrees one or two members of the party succeeded, with- 
out accident, in reaching the main opening, which was about five 
feet in diameter. Regard for personal safety, however, soon 
overcame scientific curiosity, and the retreat was accomplished by 
separate routes in the same cautious manner, to avoid getting too 
much weight upon any one place. The waters were found to be 
impregnated with soda, lime and borax. 
In the immediate vicinity of the hot springs were found numer- 
ous concretions, either on the surface or slightly imbedded. 
These had generally a prolate spheroidal form, although many 
eccentric shapes were seen. About half a mile out in the salt 
marsh was a remarkable spring (Fig. 5), nearly twenty feet in 
` diameter. The water rose to the height of several inches above 
Fig 4 Boiling Spring: 
the general surface, and was retained by a ring of earth elevated a 
foot above the terrain and thickly set with //es, a kind of rush, 
whose verdancy contrasted strangely with the sombre gray 
around, and gave to it the appearance of a miniature oasis. 
The water was quite clear and nearly fresh ; this latter property 
was probably only apparent from the contrast, after imbibing 
the more brackish water of the other springs ; its interior cylin- 
drical walls extended to a depth of about five feet, below and 
under which, as far as could be reached by a pole, nothing like 
earth could be felt. There appeared to be a subterranean lake be- 
neath the salt-marsh, of which this spring was the only visible 
portion. As to its depth we had no means of determining it; the 
temperature was 69° Fahr. The circumjacent earth was a mere su- 
_ *perficial crust, five or six inches thick, which was springy beneath 
-our tread, and breaking through which one sank into the viscous _ 
