EXAMINATION OF JALAP RESIN. 
27 
lies. It does not crystallize either from the alcoholic or 
from the aqueous solution ; it dissolves in acetic acid and in 
cold nitric acid without decomposition. Water and ammo- 
nia do not again precipitate it. Like rhodeoretine it be- 
comes colored of a beautiful carmine red after a few mi- 
nutes with concentrated sulphuric acid ; and it likewise de- 
posits after decomposition a brownish-black resinous mass, 
with the same peculiar odour; at 212° it cakes together ; 
some few degrees above this temperature it melts to a yel- 
low fluid. The pulverized acid, dried at 212°, was burnt 
with chromate of lead, and afforded — 
Carbon 55.10 55.16 42 = 3185.8 55.54 
Hydrogen 8.28 8.39 36 449.3 7.83 
Oxygen 36.62 36.45 21 2100.0 36.63 
Potash Salt. — For the preparation of this salt a quan- 
tity of rhodeoretine was conveyed into a boiling solution of 
carbonate of potash, in which it dissolved tolerably easy 
with a yellow color. The solution was then evaporated to 
dryness in the water-bath, and the dry mass extracted with 
absolute alcohol. The potash compound dissolved in it, 
and the excess of carbonate of potash remained undissolved. 
The alcoholic solution was evaporated to dryness ; the dry 
pulverized salt had a faint yellowish color, and dissolved 
both in alcohol and readily in water; the aqueous solution 
had a bitter taste and an agreeable quince-like odour. 
Heated on platinum foil, it burnt with the same bright flame 
as rhodeoretine. 
' Barytes Salt. — A certain quantity of hydro-rhodeore- 
tiue was dissolved in water, a slight excess of barytes wa- 
ter added to the solution, and the whole then evaporated 
until the excess of barytes was converted into carbonate, 
and the liquid no longer had an alkaline reaction; it was 
then filtered and evaporated to dryness in the water-bath. 
Dry and pulverized, the salt forms an almost perfectly 
white powder, which is easily soluble in water and alcohol, 
but is precipitated from the aqueous solution by absolute 
