379 A COMPENDIUM OF 
less exposed too long to the air. Specific grav- 
ity between 0.88 and 0.90, boiling at 365° F. 
Like all these volatile substances, it is made up 
of two distinct oils, one of which is a true hy- 
drocarbon. On exposure and by heating with 
caustic potassium, Stearoptene is deposited. 
The yield of oil is about 1 per cent—that is, one 
pound of the herb produces only one drachm of 
the oil. Itis frequently adulterated with tur- 
pentine; this can be detected by shaking the 
suspected oil with equal parts of alcohol; the 
turpentine is left and the oil dissolved, and 
thus the fraud exposed. Like the herb, the oil 
is stimulating and carminative in its action, and 
may be given in doses of 3 to 6 drops (0.18 to | 
0.36 gram). It is rarely if ever given alone, 
but forms an ingredient in the following com- 
pounds, which are officinal: LINIMENTUM SAPONIS, 
SPIRITUS ODORATUS, and TINCTURE LAVENDUL& 
composira. When pure, the oil makes an ex- 
cellent addition to perfumes. 
Oleum Rutz, Rue Oil. Distilled from the 
leaves and tops of the Rutz Graveolens.—Nat- 
ural order Rutacez, or Rutexw. This volatile 
oil is of a pale-yellow color, with a characteris- 
tic odor of the plant; taste acrid and bitter. Ac- 
cording to Mr. Strecker, it is chiefly composed 
of a substance termed Methyl nonyl-Ketone, 
CH, COC,CH,,. This Ketone is said to be 
analogous to Acetone, CH, CO, C, H,,, and 
yields by the action of acid nitric, pelargonic 
acid, which is much usedin the preparation of 
the artificial fruit essences, and known in com- 
merce as pelargonic ether. The oil has a spe- 
cific gravity of about 0.88, and congeals at or 
