182 PROCEEDINGS OP THE AMERICAN ACADEMY 



the lithium chloride is an obstacle ; and in case potassium is to be 

 separated from large amounts of lithium by precipitation as potassio- 

 platinic chloride, the concurrent precijiitation of a similar salt of 

 lithium, to which Jenzsch * has directed attention, may be the occa- 

 sion of inexactness. So, the intrinsic unsatisfactoriness of indirect 

 methods quite aside, it appears that in following Bunsen we have by 

 no means all that is to be desired in an analytical method. 



In looking about for better means for the separation of lithium 

 from sodium and potassium, certain preliminary experiments on the 

 behavior of the chlorides of these elements toward amyl alcohol gave 

 very encouraging indications, and subsequent quantitative tests have 

 borne out the hope that a successful method of separation might be 

 based upon these relations. 



In amyl alcohol the chlorides of sodium and potassium are highly 

 insoluble, lithium-chloride dissolves freely, and the attraction of amyl 

 alcohol for water is so slight and its boiling point so far above 100° C. 

 that the latter may be expelled without difficulty by the aid of gentle 

 heating. 



When amyl alcohol is poured into a solution of lithium chloride in 

 water the liquid forms two layers, the aqueous solution of the salts at 

 the bottom and the amyl alcohol now carrying a little water above. 

 With the application of heat, the water evaporates slowly, then boils, 

 and, passing through the alcohol, escapes, until toward the end of the 

 operation the residual lithium chloride collects in a viscous globule, 

 and finally dissolves with the exception of a slight incrustation. If 

 now the alcohol is cooled and a drop of strong hydrochloric acid added 

 and brought in contact with the deposit, and the boiling repeated, the 

 solution is complete. This deposit I take to be lithium hydrate, re- 

 sulting from the decomposition of the chloride by the protracted action 

 of water at a temperature near its boiling point. The small amount 

 of water which is added in and with the hydrochloric acid seems to 

 exert no unfavorable influence, but rather to be beneficial in hasten- 

 ing the solution of the residue by securing immediate and sufficient 

 contact. 



In hot amyl alcohol, lithium chloride appears to be a little more 

 soluble than in the same reagent at ordinary temperatures, but the 

 solubility uuder the latter condition only was determined. By boiling 

 the solution until turbidity began to show, cooling, filtering, and then 

 evaporating a known volume of the concentrated solution to dryness 



* Pogg. Ann., civ. 102. 



