ON EUPATORIUM PERFOLIATUM. 
209 
After the resin had ceased to precipitate, the clear liquor was 
decanted, decolorized by purified animal charcoal and evaporated, 
when a matter similar to that obtained in experiment first re- 
mained, but so contaminated with acetate of soda, derived unsus- 
pectingly from the acetic acid used, that it was rejected. 
On examining the chlorophylle upon the filter, it was found to 
contain a white matter; alcohol was added to wash out the chlo- 
rophylle, when it remained as a white crystalline powder, inso- 
luble in water, alcohol, ether and liquor potassa, but soluble in 
nitric acid, producing a yellow color. Exposed to heat upon a 
plate of glass, it fused and was decomposed, giving off an odor 
similar to acrolein, and apparently leaving no residue. The 
amount obtained was quite small. 
Expt. 3. — The aqueous extract obtained from four ounces as 
mentioned in experiment first, was treated with deodorized alco- 
hol, which took up the bitterness and left gum, together with in- 
soluble extractive, coloring matter, chloride of potassium and 
nitrate of potassa. The resulting tincture was treated with an 
excess of subacetate of lead, the excess of lead thrown down by 
sulphuretted hydrogen, and the liquid filtered ; the clear solution 
was evaporated to dryness in a water bath to drive off sulphuretted 
hydrogen and acetic acid, and then redissolved in a small quantity 
of alcohol and reduced to a thick syrupy consistence. It was then 
treated with ether, which took up the bitterness, leaving a dark 
brown residue, soluble in water and alcohol, and precipitable by 
subacetate of lead. The ethereal solution was decolorized by 
purified animal charcoal and left to spontaneous evaporation. 
The result was a yellowish brown substance, similar to that ob- 
tained in experiment first, of a sweet odor, v,ery bitter taste, and 
on the sides of the evaporating dish presenting the appearance of 
crystallization. A portion from the sides appeared, under the 
microscope, studded with numerous minute feathery crystals. A 
portion exposed to heat on a plate of glass, fused with a slight 
elevation of temperature, and was ultimately decomposed and 
burned off, leaving apparently no residue. When inflamed it 
burned with much smoke, leaving a bulky charcoal. 
From these characters it would appear to be a resin, but its 
slight solubility in water, and also its affording evidences of crys- 
tallization, seem to distinguish it from resinous bodies. 
VOL. xiv. 19 
