J. M. Ordway on Waterglass. 189 
16.—100 g. of 25 p.c. NaSi,, with 200 g. of 25 p.c. NaCl, gave 11°3 g. 
of a soluble curd containing 10-7 p. c. of mother-liquor and 54°7 p.c. 
of Na 19.6. 
The mother-liquor contained 6°3 p. ¢. of NaSi;.g, 
16.—100 g. of 25 p.c. NaSi,, with 100 g. of 25 p.c. NaCl, yielded 6-25 
g. of a hard pressed. mass containing 18 p.¢. of mother-liquor and 
50°3 p- ¢. of Na ig.5. 
The mother-liquor contained 10:5 p. ¢. of NaSij.9. 
17.—In several different trials, chlorid of sodium had little or no effect 
on sesquisilicate of soda. 
18.— . ¢. KSigs, with 100 g. of 25 p.c. KCl, gave 21:2 g. 
of a hard pressed, soluble product containing 11°5 p.¢. of mother- 
liquor and 59°6 p. c. of K3i,. 
The mother-liquor contained 6°35 p. c. of KSi,. 
€ have a deposit of 126 g. of dry K&i,, while in 6,— 
the parallel soda experiment,—19°2 g, of dry NaSie.. were thrown 
wn. A potash silicate is therefore less precipitable than the 
corresponding soda waterglass. 
© two following trials were made with reference to Ber- 
ig doctrine of the partition of bases among contending 
acids, 
19.—100 g. of 25 p. ¢. NaSio.s—containing 5:4 g. of soda,—were mixed 
with 50 g. of 25 p. c. KCl,—whie 79 g. of 
g. of 25 p.c. NaSiog were stirred 61 g. of 25 p.c. KCl 
mixed with 41 g. of 25 p.c. NaCl,—so that in the sum of the in- 
Similar results were obtained in experiments made with sili- 
Cate of potash and chlorid of sodium, or with a silicate of one 
alkali and an acetate of the other. 
_ The alkaline acetates are rather more efficient than the chlo- 
Mids, in throwing down waterglass. Owing to the alkaline reac- 
hon of the acetates themselves, it is not easy to analyze with 
accuracy the contaminated products, and the results given below, 
claim only an approximation to correctness. The potash or sod 
Was determined by neutralization with a standard chlorhydric 
acid. The tested stuff being dried down with an excess of the 
Same acid, the quantity of chlorid in the residue, minus the 
amount of chlorid due to the alkali of the silicate, indicated the 
pace of acetate. ; a = 
—100 g. of 25 p. c. NaSigs, with 200 g. of 25 p. c. _gave 39° 
8. of a Rend hiesta: soluble mass, containing 59 p. c. net of NaBSiz-¢o. 
AM. Jour. Scr.—Secoxp Sertes, VoL. XXXV, No. 104.—Manca, 1863. 
25 
