BUESEKACE^l4 465resin after no more oil passes over for the purpose of obtaining a larger
yield, and the distillation is then continued. The constituents of myrrh
oil identified by him are : cuminic aldehyde, C 10 H 12 O (up to 1 per cent.),
boiling-point 116° (12 mm. pressure); oxime, melting-point 56°; semi-
carbazone, melting-point 201°.—Acids: Of these, only acetic acid and
palmitic acid (melting-point 62°) were detected with certainty. Both are
present in old oils in the free state, whilst freshly distilled myrrh oil
contains the acids as esters.—Phenols (about 1 per cent.): eugenol
l
(about 0
- 23 per cent. ; benzoyl compound, melting-point 69°), and a
 small quantity m-cresol were detected.—Hydrocarbons: Fractional dis-
 tillation over sodium yielded four hydrocarbons (terpenes) of the formula
 C 10 H 16 (all of which, however, were not found in every oil examined), of
 which three were identified; pinene (nitrosochloride, melting-point 103°;
 nitrolbenzylamine and nitrolpiperidine); dipentene (tetrabromide, melt-
 ing-point 124°); limonene (tetrabromide, melting-point 104°); the fourth
 hydrocarbon probably belongs also to the limonene group (AO + 80°,
 tetrabromide, melting-point 115°, and monohydrochloride, melting-point
 6°) but could not be identified. Sesquiterpenes : probably cadinene is,
 present, and a second sesquiterpene of specific gravity 0'911 at 21°, and
 optical rotation + 30*4°.
 Friedrichs
 l
 distilled an oil from picked myrrh, which had the follow-
 ing characters:—
Specific gravity.
Optical rotation ....
Refractive index ....
Acid number .....
Ester ,, ...vity. 1-011- 73-8
 1-5359
 6-15
 47-6
 No eugenol could be detected, but meta-wesol was present. Cumic
 and cinnamic aldehydes were also found to be present. A sesquiterpene
 having the following characters was also isolated :—
 Boiling-point
 Specific gravity.
 Optical rotation.
 Refractive index
 Molecular refraction
130° to 136° at 16 mm.
0-943 at 20°- 14° 12'
 1-5125
 64-98
 To this body he assigns the name herabolene.
 Traces of formic and acetic acids were also found, and a non-volatile
 acid melting at 159°, and an acid of the formula C 16 H 21 O 3. COOH,
 melting at 236°, which he names myrrholic acid.
 Bisabol Myrrh.—The principal plant yielding this resin is probably
 Commiphora erythraea.
 Tucholka
 2
 has extracted the essential oil from a Bisabol myrrh coming
 from the interior of the Somali country, by removing it from the alcoholic
 solution of the resin by means of petroleum ether. The oil was purified
 by steam distillation, and then had a light yellow colour, specific gravity
 •8836, and optical rotation - 14° 20'. It boiled at ^20° to 270°. The
 yield was 7
- 8 per cent. By means of dry hydrochloric acid gas, a crys-
 talline hydrochloride was separated, which, on treatment with boiling
 acetic solution of sodium acetate, set free a hydrocarbon which the above-
 named investigator terms bisabolene. This hydrocarbon had a specific
 gravity -8914 and boiled at 260°. The same chemist suggests the unlikely
 formula C 50 H9(3O for the residual portion of the oil.
(^1) Arch, der PJwrm., 245 (1907), 427.
VOL. i.. 30
(^2) Arch. Pharm., 235, 289.
