176 Dr. T. Anderson on the Products of the 



periments, and those of certain of the organic bases contained 

 in it. 



The products of jjie destructive distillation of animal mat- 

 ters were long since employed in medicine, and were obtained 

 from all parts of the body, and from almost every section of 

 the animal kingdom ; but these afterwards entirely gave way 

 to the Oleum Cornu Cervi, which, as hartshorn is entirely free 

 from fatty matters, must necessarily be the pure product of 

 decomposition of the gelatinous tissues. The more volatile 

 portions of this oil, separated by distillation with water, and 

 purified by numerous rectifications, constituted the Oleum 

 Animale Dippellii of the older pharmacopoeias. These sub- 

 stances would in all probability have been the most convenient 

 crude materials for my experiments ; but as they have long 

 since ceased to be employed, and cannot now be obtained except 

 by going through the tedious and disagreeable process for their 

 preparation, I have made use of the bone-oil of commerce, 

 which is prepared on the large scale by the distillation of bones 

 in iron cylinders, and can be had in any quantity from the 

 manufacturers of ivory-black. This oil appears to differ in no 

 respect from the true Oleum Cornu Cervi, and, like it, is the 

 product of decomposition of the gelatinous tissues only ; for 

 previous to distillation the bones are boiled in a large quantity 

 of water, by which means both the fatty matters and also a 

 certain proportion of the gelatine are separated. They are 

 then dried, packed in the cylinders, and distilled at a heat 

 which is gradually raised to redness. The oily product of 

 this distillation is sepai'ated from the watery portion, and, 

 after rectification, forms the bone-oil of commerce ; though 

 in some instances this latter distillation is dispensed with, and 

 the product of the first made use of without any further puri- 

 fication. 



Bone-oil, as supplied by the manufacturer, has a dark 

 brown, almost black colour, with a somewhat greenish shade, 

 and perfectly opake in the mass ; but when spread in a thin 

 layer on a glass plate, it is seen to be brown by transmitted 

 light. Its specific gravity is about 0*970. Its smell is pecu- 

 liarly disagreeable, and is mixed with that of ammonia, which 

 is always present, though sometimes in so small quantity that 

 its odour is disguised by that of the oil itself, and is only ren- 

 dered apparent by distillation. A piece of fir- wood moistened 

 with hydrochloric acid, and held over the mouth of a vessel 

 containing it, rapidly acquires the dark reddish-purple colour 

 which is characteristic of the pyrrol of Runge. Acids agitated 

 with the oil acquire a brown colour, especially on standing, 

 and extract the bases contained in it; but if the quantity of 



