fome chemical Experiments on Tabafheer. 375' 
dually heated till red hdt, did not become in the leaf! black, 
or lole much of its weight, a proof that no acid of fugar had; 
fixed in it. 
With liquid alkalies . 
§ IX. (A) Some liquid cauftic vegetable alkali being heated 
in a phial, Tabafheer was added to it, which diffolved very 
readily, and in confiderable quantity. When the alkali would 
not take up any more, it was fet by to cool, but was not found 
next morning to have cryftallized, or undergone any change, 
though it had become very concentrated, during the boiling,, 
by the evaporation of much of the water. 
(B) This folution had an alkaline tafte, but feemingly with 
little, if any, caufticity. 
(C) A drop of it changed to green a watery tincture of 
dried red cabbage. 
(D) Some of this folution was expofed in a fhallow glafs 
to fpontaneous evaporation in a warm room. At the end of a 
day or two it was converted into a firm, milky jelly. After a 
few days more, this jelly was become whiter, more opaque, 
and had dried and cracked into feveral pieces, and finally it be- 
came quite dry, and curled up and feparated from the glafs. 
The fame change took place when the folution had been di- 
luted with feveral times its bulk of diftilled water, only the 
jelly was much thinner, and dried into a white powder. 
Some of this folution, kept for many weeks in a bot- 
tle clofely flopped, did not become a jelly, or undergo any 
change. 
(E) A, 
