T. M. Chatard — Analyses of Alkali Lake Waters. ,147 



tillation, being collected and weighed in a potash bulb. For 

 the boric acid, in the water of Owen's Lake, the excellent 

 method of G-ooch* was followed ; for the Mono and Ragtown 

 waters the process of Stromeyer, with modifications of my 

 own, was used, but, though giving very fair results, the pro- 

 cess cannot be compared for ease, simplicity and accuracy with 

 the former method. 



The determination of the alkalies in such very dense waters 

 was, at first, found to be difficult, owing to the large quanti- 

 ties necessarily taken. To get determinations which shall be 

 fairly accurate when referred to a liter, portions of not less 

 than 50 c.c. should be taken, the water in all cases being care- 

 fully weighed. The amount of alkaline chlorides correspond- 

 ing to 50 c.c. of such waters is very large, and, when the final 

 evaporations are being made, there is great liability to loss, 

 owing to the formation of a salt crust on the surface of the 

 liquid and subsequent spirting caused by steam and ammonia 

 vapor produced under the crust. This takes place no matter 

 how carefully the evaporation be carried on, and many deter- 

 minations were thus lost. 



The use of hydrochloric acid enables us, however, to com- 

 pletely obviate this difficulty. The purified alkaline chlorides 

 are to be evaporated till crystallization begins ; the platinum 

 vessel is then removed from the water bath and an equal bulk 

 of very pure, highly concentrated hydrochloric acid added to the 

 solution. A copious precipitation of finely granular salts at 

 once ensues, and, on replacing the vessel on the water bath, 

 evaporation goes on quietly and rapidly, no salt crust is formed, 

 and when the final heating is given, little decrepitation occurs. 

 In this manner, it is as easy to handle several grams of chlo- 

 rides and to obtain accurate determinations as it is when we 

 have to deal with the far smaller quantities usual in mineral 

 analysis. 



Of the four lakes to be considered, the most northern one is 

 Abert Lake, in south-eastern Oregon. The sample analysed 

 was " collected by H. T. Biddle at middle of west side of lake, 

 one foot below surface, 30-40 feet from shore, September, 

 1887." The total quantity at my disposal was about 200 c.c, 

 an amount too small for any extended research, but sufficient 

 for all practical purposes. For each determination, 25 c.c. = 

 25*7792 grams were taken. 



Specific Gravity, 1-03117 at 19.8°. 



* Gooch, Proc. Am. Acad. Sci., 1886, p. 167. 



