400 RHUS VERNIX. 
lected in a phial, it retained its whitish colour, 
except at the surface, where it turned black from 
its contact with the air in the upper part... This 
juice was kept for more than two years without 
any change in its appearance. In cold weather 
it was extremely viscid, and flowed with difficulty, 
Different portions of this juice were submitted 
to chemical examination. It was perfectly insolu- 
ble in water, although upon boiling with it, it 
formed a thick emulsion. Alcohol dissolyed it 
sparingly, and the solution was rendered turbid 
by water. Ether combined with it more large- 
ly, forming a thick, opaque compound. Strong 
sulphuric acid combined with it, producing a 
black solid mass. Alkalies also combined with 
it, and a strong solution of pearl ash dissolyed.a 
portion of it, which was afterwards precipitated 
by sulphuric acid, It had an affinity for metallic 
oxyds, and powdered litharge, upon being boiled 
with it, rendered it nearly solid. In distillation 
at the heat of boiling water, nothing came over 
except a slight film upon the. surface of the wa- 
ter. When the heat was raised to the boiling 
point of the juice, a quantity of thin, blackish, yol- 
atile oil came over, which dried up on being ex- 
posed to the air, leaving a slight coating on the 
‘surface of the yessel which contained it. The 
