130 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 60 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 C. A definite volume of 

 the petroleum spirit extract was evaporated, dried, and weighed. 



TOTAL SOLIDS. 



Petroleum spirit residue dried at 100 C 2.20 per cent, of solids. 



" 110 C 2.01 " " " 



^7 9 " " 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 



