474 J. M. Ordway — Waterglass. 



gave no precipitate, but alcohol threw down a curd which when 

 hard pressed weighed 21 g. and contained 65 p. c. of 5(Li„O3Si0 o ) 

 + 6(Na„O3Si0 o ). This dissolved readily in a little more than 

 twice its weight of water. 



2. 40 g. of the 31 p. c. lithium chloride solution with 100 cc 

 of the same sodium trisilicate gave 17 g. of cake showing 55 p. c. 

 of 3(Li n O , 3SiO„) + Na„0 , 3SiO„, and soluble in 1*6 times its weight 

 of water. 



3, a. 86 g. of a 20 p. c. lithium chloride solution were put with 

 154 g. of a 20 p. c. solution of Na„O4Si0„. The cake weighed 

 48 g. It contained gross 56 p. c. of 7"(Li o 0-48i0,) + 6(Na o 0-4Si0 n ). 

 Net 54-4 p. c. of 7(Li a O-5SiO a )+6(Na 2 0-4Si0 3 ). 



3, b. The cake of a was dissolved in twice its weight of water. 

 133 g. of this liquid with 75 g. of the lithium chloride solution 

 gave 46 g. of cake containing gross 51*7 p. c. of 7(Li„O4Si0„) 

 + 3(Na 2 0-3SiOj ; net 50'7 p. c. of 9(Li 2 O4Si0„) + 5(Na 2 0-5SiO;j. 



3. c. The cake of b treated with 102 g. of water left a very 

 little sediment; 120 g. of the filtered solution with 60 g. of a 25 

 p. c. lithium chloride solution gave 49 g. of cake not entirely 

 soluble in 150 g. of water. The dissolved portion contained net 

 42 p. c. of 2(Li o 0-4Si0 2 ) + (Na o 0-4Si0„). 



4. 110 g. of a 12 p. c. solution of ]S f a 2 03SiQ 2 with 40 g. of a 

 31 p. c. lithium chloride solution yielded a curd containing 54 

 p. c. of 3(Li 2 0-3Si0 2 ) + Xa„0-3Si6 2 . This dissolved readily in 

 twice its weight of water. 



5. 50 g. of a 20 p. c. solution of K 2 O2Si0 2 with 30 g. of an 18 

 p. c. solution of LiCl gave 7 g. of cake containing 40 p. c. of 

 Li 2 0-2SiO„ + K„0-2Si0 2 . 



6. 30 g.'of a" 20 p. c. solution of K 2 O3Si0„ with 30 g. of an 

 18 p. c. solution of LiCl gave 10 g. of cake mostly soluble in 

 4 parts of water. The clear solution contained 7 p. c. of 

 3(Li 2 0-3Si0 2 ) + 2(K 2 0-2Si0 2 ). 



So we may make an endless variety of mixed or double sili- 

 cates of lithium and sodium or lithium and potassium. Start- 

 ing with a given potassium or sodium waterglass, the relative 

 proportion of lithium may be gradually increased by dissolving 

 the successive cakes and reprecipitating with lithium chloride. 

 And until we get beyond a tetrasilicate the deposit is com- 

 pletely soluble in a small amount of water. Were the precip- 

 itations continued, it would be necessary to add lithium 

 hydroxide to the later solutions to keep them from being too 

 silicious. But an attempt to eliminate the sodium entirely 

 would probably develop into an infinite series of trials. 



A saturated solution of the lithium hj'droxide contains but 

 a small percentage of the alkali and to concentrate a siliceous 

 liquor which has been much diluted with such a solution we 

 cannot resort to evaporation by heat. For it has been found 

 that when any sodium lithium waterglass is heated a precipi- 



