188 GEOLOGICAL SURVEY OF THE TERRITORIES. 



No. 2. From alkaline effloresence on clamp ground, seven miles west 

 of St. Mary's Station, in the Sweetwater Valley : 



Per cent. 



Sulphate of soda, (Na O, S 3 ), to -• 88.93 



Chloride of sodium, (Na, CI), to 11. 63 



100, 56 



No. 3. From deposit near Pacific Springs : 



Per cent. 



Sulphate of soda, (Na O, S 3 ) 82.23 



Chloride of sodium, (Na, CI) 3,95 



Carbonate of soda, (by loss) 14. 82 



100. 00 



No. 4. From deposit by evaporation of Alkaline Pond, near Big Sandy 

 Eiver. 

 No. 4, (a.) From upper part of bank, where deposition commenced : 



Per cent. 



Sulphate of soda, (Na O, S 3 ) 64.65 



Chloride of sodium (Na, CI 35.46 



100. 11 

 No. 4, (&.) Taking half way between upper and lower limit of deposit: 



Per eent. 



Sulphate of soda, NaO, S 3 ) }.. 94.92 



Chloride of sodium, (Na, CI) 5. 23 



100. 15 



No. 4, (c.) From lowest part of pond, when last deposition took place, 

 consists of slender orthorhombic prisms of pure sulphate of soda — she- 

 nardite : 



Per cent. 

 Sulphate of soda, (Na O, S 3 ) 100.00 



All the specimens appear to be absolutely free from any salts of po- 

 tassa, an examination by the spectroscope even failing to show the pres- 

 ence of that base. 



