
XII.—On a New Source for obtaining Caprice Acid, and Remarks on some of its 
Salts. By Mr Toomas Henry Rowney, F.CS. 
(Read March 17, 1851.) 
The following examination of capric acid and some of its salts, was made in 
the laboratory of Dr T. ANDERSoN, to whom I am much indebted for his kindness 
in procuring for me the materials to work upon, and also for advice during the 
progress of this investigation. Capric acid has been found by CHrvreut and 
Lerca in the butter of the cow and goat; by ReprenBacueEr,* amongst the vola- 
tile oily acids he obtained by acting on oleic acid with nitric acid; by GrrHaRDT 
and Canours,} by the action of nitric acid on the oil of rue; and by GorGery,t 
in cocoa-nut oil;—from all these sources it has been obtained only in small quan- 
tities, and always along with other acids of the series to which capric acid 
belongs. 
In the present paper I have to point out a new source for obtaining it, namely, 
the fousel oil or grain oil of the Scotch distilleries. The principal constituents of 
grain oil are water, alcohol, and the hydrated oxide of amyl.. The proportions of 
these constituents vary in the oils obtained from different distilleries ; in some cases 
it is soluble in water, and then consists chiefly of water and alcohol, with a small 
quantity of the hydrated oxide of amyl]; generally, it is an oily liquid lighter than, 
and insoluble in, water. Besides the three above-mentioned constituents, other 
compounds have been found in it in smal] quantities. Muxprer found cenanthic 
acid, and Korss|| found margaric acid. In the oil examined by myself, an acid 
was found, which analysis proved to be capric acid. In what state it exists 
in the oil, I am not able to say, but I think it most probable that it is in com- 
bination with the hydrated oxide of amy]. 
To obtain the capric acid, the grain oil was distilled with a thermometer 
placed in the tubulure of the retort, and the distillate collected in separate re- 
ceivers. The first portion consisted of water, alcohol, and the hydrated oxide of 
amyl; the second portion was the hydrated oxide of amyl, and a dark-coloured 
residue was left. This residue was oily, it had a very disagreeable smell, and 
was insoluble in water and KO,CO,, even when boiled with a solution of the 
latter; when boiled with a strong solution of caustic potassa it is rendered so- 
luble in water. Whilst boiling, a strong smell of the hydrated oxide of amyl is 
* Journal of the Chemical Society, Part 19. + Annalen de Chemie und Pharmacie, Band 56. 
¢ Annales de Chemie et de Physique, 3d § Liebeg’s Annalen, Bd. 24, p. 248. 
Series, Tome 24. || Idem, Bd. 41, p. 35. 
VOL. XX. PART II. 3N 
