1.
2-9 per cent.
170° to 172°
0-8628- 28'12°
2.
2-6 per cent.
172'6° to 178-2°
0-8616- 26-24°
CONIFEK^E 57160° were obtained. On refractionation 4ihe oil boiled at 156° to 157°, had
a specific gravity 08682, and optical rotation - 1194°. It yielded a
nitrosochloride melting at 103° and a nitrolpiperidine melting at 118°.
Camphene could not be detected. (3) /2-Pinene. —A fraction was obtained
which boiled at 164° to 166°, and had specific gravity 0872, and optical
rotation - 1719°. This was easily oxidised by means of alkaline per-
manganate to nopinic acid, which melted at 126°. This fraction was
therefore /3-pinene. (4) Dipentene and Limonene.—Two fractions were
•obtained, having the following characters :—
Weight
Boiling-point ....
Specific gravity ....
Optical rotation....
The former fraction yielded a dihydrochloride, melting sharply at 50°
after several recrystallisations from alcohol. The latter fraction yielded
a tetrabromide, which melted at 117° to 119°, or after further recrystallisa-
tion at 121° to 122°. It is probable that this fraction contains both di-
pentene and laevo-limonene. (5) Borneol.—The oil recovered from the
saponified ester fraction was distilled. The fraction 208° to 213° had a
rotation of - 1942°. It was treated with phthalic anhydride for eight
hours. The resulting acid phthalic ester was converted into the sodium
salt and exhausted repeatedly with ether. After saponification the oil
was oxidised with chromic acid, and camphor, melting at 174°, recovered
by steam distillation. This establishes the identity of borneol. (6) .Acetic
Acid.—This acid was found to be the principal acid constituent of the
esters. (7) A green oil having a specific gravity 09370 was isolated,
but not identified. The approximate amounts of the above compounds
present are as follows : a-pinene, 25 per cent.; /3-pinene, 48 per cent.;
dipentene and limonene, 6 per cent.; furfural, traces; esters, 61 per
'Cent.; free borneol, 65 per cent., green oil, 3*0 per cent.
Pseudotsuga taxtfolia is also known as P. Douglasii. According to
Henry and Floodl the Douglas fir growing in Oregon is rightly described
under this name, whilst the Colorado or blue Douglas fir is P. glauca.
C. T. Bennet has examined the oils distilled from material grown in
England, of both plants, and reports upon them as follows :—
" OIL FROM LEAVES OF THE OREGON DOUGLAS FIR.
" 1. 50 Ibs. of leaves of young trees growing at Avondale, sent in
August, 1919. When distilled less than 0*01 per cent, of an oil with a
very aromatic odour was obtained—a quantity too small for examination.
" 2. 50 Ibs. of leaves of old trees growing at Buckhold, Berks, sent in
November, 1919, when distilled yielded 0*11 per cent, of oil having the
following characters:—
Specific gravity 0-876
Optical rotation ........ — 7°
Refractive index 1-4835
Esters as bornyl acetate 12*4 per cent.
"The ester content is much lower than that of the Colorado Douglas
fir oil, but the odour is more fragrant. The oil contains dipentene or
limonene, but if pinene is present, the quantity is very small, as prac-
tically nothing distils below 175°.(^1) Proc. Roy. Irish Acad., May, 1920.