324 EXPLORATIONS ACROSS THE GREAT BASIN OF UTAH. 



Salt is found in great quantity. As the water of Salt Lake is a nearly concen- 

 trated pure brine, salt can be got there at a trifling expense. (See Captain Stansbury's 

 Report.) ( >ther saline lakes contain impurities from which the salt cannot be freed so 

 easily. Some ot it was observed in many springs, round which it accumulates, but 

 there is usually too little of it to be of much importance. 



.Near the eastern rim oi the basin, in the Wahsatch Mountains, large masses of 

 rock-salt are found, partly in pure transparent crystalline pieces, partly strongly mixed 

 with ved clay, with which it is associated. The specimens in the collection have been 

 obtained by the kindness of ( Jcneral A. S. Johnston and Colonel Crosman. Salt is thus 

 found in the mountains bordering San Pete Valley on the east, some 20 miles south 

 of the Mormon settlement of Manti (in the latitude of Sevier Lake) ; also in the so- 

 called San Pete Canon, and still further south, near Captain Gunnison's trail. I have 

 not examined any of these localities, and can, therefore, not decide to which geological 

 formation the salt belongs. The limited information which I have been able to obtain 

 in regard to it, and considerations of a general geological character, seem to indicate 

 that it belongs to those strata which, in the neighborhood of Salt Lake and Utah Lake, 

 are confined to the eastern portion of the Wahsatch range, but seem to cross it further 

 south toward Little Salt Lake. They have been spoken of in section IV, and may 



Various other salts are found in large quantities. 



Sulphate of soda was received by Dr. Schiel as coming from the bottom of Salt 

 Lake. (See Captain Beckwith's Pacific Railroad Report.) A salt, probably the same, 

 forms heavy deposits on the eastern shore of Utah Lake, near Springville. Our speci- 

 mens have not yet been analyzed. It is a useful article in various manufactures, 

 especially that of soda, 



Sulphate of magnesia enters largely into the composition of many salts and saline 

 water in that part of the country. It is formed by the decomposition of various 



^ Xatire alums were observed in several places. They are formed by the decom- 

 position of inetamorphie slates and other rocks, etc., which contain pyrites. Captain 

 Stansbury mentions alum from the northern end of Salt Lake. Dr. Schiel mentions a 

 magnesian alum. All those which I have examined are magnesian alums, in which 

 the sulphate ot magnesia replaces, in a great measure, the alkaline component, which, 

 ilum, is potassa. No complete analysis has been made by us of any 

 in the collection a specimen from Tuilla Valley, obtained 

 >nel Crosman, and one from the neighborhood of Little Salt Lake, by Dr- 



of these alums. 



Brewer. 



The saleratus-ciay, which I have mentioned already, seems also to contain it in 

 considerable quantity. A specimen of this clay from Camp Floyd is of oray color 

 full of white crystallizations and nodules of saline substances, and sometimes\vhitish 

 throughout. It is also formed by an accumulation of salts from the decomposition of 

 rocks in the clay. The soluble portion contains a little common salt, a great deal of 

 sulphate of magnesia, some sulphate of lime, and a little soda. Probably the sulphate 



