i3o PLANT AND ORGANIC CHEMISTRY 
holic solution of the petroleum spirit residue was submitted 
to a fractional precipitation with an alcoholic solution of mag¬ 
nesium acetate. The first precipitation obtained was puri¬ 
fied by boiling alcohol; it was an opaque scaly crystalline 
solid which melted at 85° C. The second precipitation yielded 
traces of a white amorphous substance. The third precipi¬ 
tation resulted from adding strong ammonia water to the 
magnesium acetate solution, and the purified residue melted 
at 6o° C. 
Negative tests for alkaloids followed an examination of 
the aqueous treatment of the petroleum spirit residue. 
Extract (3), Green Part oj the Leaf. 
The method of extraction was the same as that used in the 
previous extractions. The extract was clear, pale green in 
color, and non-fluorescent. It was colored by a small quan¬ 
tity of chlorophyll, which the petroleum spirit dissolved. The 
liquid was acid in reaction. A drop of it left a permanent stain 
on blue paper, when evaporating. The extract was evaporated 
at the ordinary temperature, and the residue was a dark green¬ 
ish-yellow semi-fluid substance. The solidifying point was 
taken. It was found to be about 15 0 C. A definite volume of 
the petroleum spirit extract was evaporated, dried, and weighed. 
TOTAL SOLIDS. 
Petroleum spirit residue dried at ioo° C.2.20 per cent, of solids. 
“ “ “ iio° C.2.01 “ “ “ 
0.19 “ “ loss. 
The petroleum spirit residue was identified as a fixed oil 
with a small amount of chlorophyll that had been brought 
into solution by it. It was soluble in cold 83 per cent, alcohol, 
95 per cent, alcohol, absolute alcohol, amyl alcohol, ether, 
acetic ether, chloroform, benzole, carbon di-sulphide and 
glycerin. It was also soluble in oil of turpentine, almond oil, 
ammonium hydrate, mercuric chloride, and slowly soluble 
in acetic acid. Concentrated nitric acid, and hydrochloric 
