276 T>r. Stenhoiise on Oil of Assqfcetida, S,-c. 



smell. The quantity of oil which the resiii yields, varies ac- 

 cording to its freshness. A pound of the resin generally yields 

 about one-third of an ounce of oil, which is obtained by distilla- 

 tion with water in the usual way. It is advisable to mix the 

 resin with pounded glass, as this prevents the resin from ad- 

 hering to the bottom of the retort, and both hinders it from 

 burning and diminishes the violence of the succussions with 

 which the distillation M'ould otherwise be attended. The oil 

 has usually a slightly yellowish tint: its specific gravity is 

 0*9428 at 60° F. ; its taste is first mild and then acrid. When 

 exposed for some time to the air it oxidizes, and a resinous 

 matter forms in it. In order to prepare it for analysis, the oil 

 which had been twice distilled with water to remove all the 

 resin was rectified over chloride of calcium on the oil-bath. 

 Its boiling point is by no means constant; it began to boil at 

 325° F., and continued to rise till it reached 370° F. The re- 

 ceiver was changed three times during the distillation, and the 

 products separately collected and analysed. The presence of 

 sulphur in oil of assafoetida was first noticed by Zeise. It dif- 

 fers from oil of mustard, by containing no nitrogen. The 

 carbon and hydrogen were estimated by analysis with oxide 

 of copper, and the sulphur was determined by passing the oil 

 in vapour over a mixture of nitre and carbonate of baryta at 

 a red heat. The following are the results : — 



(1.) Analysis of 1st quantity, 0-2967 oil, boiling at 325° F., 

 gave 0"710 carbonic acid, and 0*2625 water. 



(2.) Analysis of 1st quantity, 0-2915, gave 0-6935 carbonic 

 acid, and 0-253 water. Per cent. 



0-382 oil gave 0-635 sulphate of baryta = 22-93 sulphur. 



0'391 oil gave 0-639 sulphate of baryta = 22-54 sulphur. 



Carbon . • • • 

 Hydrogen . • 

 Sulphur . • • 

 Oxygen • • . 



100-00 



(].) Analysis of 2nd quantity of oil, boiling at 341° F., 

 0-2312 gave 0*523 carbonic acid, and 0-1967 water. 



(2.) Analysis of 2nd quantity, 0-2728 gave 0-6177 carbonic 

 acid, and 0-2224 water. 



(3.) Analysis of 2nd quantity, 0-2889 gave 0*6461 carbonic 

 acid, and 0-2447 water. 



0-413 oil gave 0-601 sulphate of baryta = 20-12 per cent, 

 sulphur. 



0-421 gave 0*610 sulphate of baryta = 19*99 per cent, 

 sulphur. 



