Richards and Palmer—Antimony Tannate. 197 
bly, three pheno] H’s replaced by Sb as well as three acid H's. 
This formula is deduced from the following analyses of anti- 
mony tannate. All the tannates described in this paper were 
prepared in the same manner. e solution, containing five 
to ten one of tannic acid per liter, was heated to 60° CG. in a 
¢.c. of ammonium acetate per liter. After the whole was 
shaken and allowed to settle, it was filtered and dried at 100° C. 
to 105° C. for three or four days i in an ordinary air-bath. The 
bulky, yellowish-white, gelatinous precipitate at first formed 
became, when dried, yellowish to reddish-brown, transparent, 
amorphous, and broken into small angular fragments. 
Antimony Tannates. 
Sb. e j 
Per cent. Per cent. Per cent. 
2°91 
From purified tannin 20°6 37°53 2°98 
$761 2°78 
From unfiltered tannin 37°95 2°71 
From filtered tannin 89°30 2°86 
88°32 2°88 
From nutgalls 20°5 38°47 2°81 
38°14 2°92 
From sumac, No, I 39°60 2°70 
II 39°54 2°74 
Ii 20°1 40°51 2°92 
The antimony was determined as a sulphide, and the calcu- 
lated pas are probably a little too high. 
to the process of titration, our first experience coincided 
With the statement of Gauhe (Zeitschrift fir Analyse, 1863, 
ili, page 122), that the end of the reaction was difficult £ to seize, 
and that the dilute solutions remained turbid. Even after we 
und an indicator, the process in our hands gave varying 
results with varying quantities of ammonium chloride and with 
different proportions of water. 
e then made a series of tests with other substances, viz: 
alin: salts of sodium, ete., as precipitating agents. The one 
chosen as a result of these tests was ammonium acetate, prepared 
by mixing in the right proportion glacial acetic acid and stron 
ammonia water of ign strengths.* 1 c.c. of this preparation 
added for every 25 or 80 ¢.c. of the total bulk, will give a clear, 
Without sta liquid after standing a few minutes. 
—— stating in detail the steps of the investigation, we 
process as we now use it. 
e used acetic aci nt gH4 d 
a er et Ni aha eh gn MEH hoe 
Am. Jour, es a Vou. XVI, No. 98.—Sepr., 1878. 
