Richards and Palmer—Antimony Tannate. 363 
sponding in dullness to that produced by gallic acid, and on 
the alumina a dull reddish-brown. To the first class belong 
nut-galls, sumac, sweet-fern leaves, bark of quercitron, black 
oak, white oak and chestnut oak and bearberry leaves; to the 
other, hemlock, catechu, kino, fever bark, cinchona bark and 
congo tea. For our further investigation we took sweet-fern as 
the type of the former, and hemlock as that of the latter class. 
The yellow in sweet-fern seems closely allied to, if not iden- 
tical with the quercetin derived from oak-bark. A solution 
of sweet-fern guarancined (i. e., boiled with very dilute sul- 
lack gummy mass being formed, and the solution depositing 
yellow flakes which dye intensively. 
wo pieces of cloth of equal size, the one dyed with one 
gram of sweet-fern leaves, the other with one gram of quer- 
citron-bark, showed rather more tannin and less yellow for 
the sweet-fern, and more yellow and less tannin for the 
quercitron. 
A single trial of the amount of yellow in sweet-fern, by 
weighing the antimony-tannate which had carried down the 
yellow with it, and which had been added in known quantity 
gave 2°5 per cent, and the amount of tannin in the filtrate had 
decreased about three of the eight per cent. This indicates 
. 
treatment with the antimony tannate was C 44°9 per cent and 
3°9 per cent. 
eppe (Die chemischen Reactionen) gives the formula of 
quercetin as CHO, and that of quercetin acid as C,;H,0,, 
which, corresponding to our formula of antimony tannate, 
would give respectively : 
Sb. Cc. H. 
Sb,(C,,H,,0.,),+6H,O .-.----- 12°52 pr.ct.50°00 3°08 
SOTHO SOLO Siig neues’ 19°49 43°13 287 
imony-tannate, 
Sb,(C,,H,0,),+6H,O...-.--.-. 18°59 38°41 274 
. The result of this is that the process of titration with tartar 
metic, when applied to the class of substances holding this 
yellow coloring principle, would give too high results) W 
