37 
free play of steam both above and below; the layer of bark was about 2 inches, a deeper layer not being 
so satisfactory in its yield of oil. It was then placed in the still and subjected to a steam distillation of 
30 lb. pressure in the boiler and 5 lb. in the still. The distilled water was white and milky in appearance, 
the oil not separating freely, its specific gravity, of course, accounting for this. The first portion of the oil 
that came over floated on the top of the water, the second sinking to the bottom ; the whole of the water 
being permeated with suspended globules of oil. Our receivers were much too shallow for this specific 
purpose, but if a deep receiver were used and fitted with a proper arrangement of taps, a return of over 
1 per cent, could be easily obtained. 
The first distillation (7th and 8th July, 1897) was made on 84 lb. of ground bark, yielding 11| oz. 
of oil, or '85 per cent. 
Second distillation (13th July, 1897) weight of bark 84 lb., yielding 13| oz. of oil, or T005 per cent. 
Third distillation (15th July, 1897) weight of bark 120 lb., yielding 144 oz. of oil, or -75 per cent. 
Total quantity of bark 288 lb., giving a yield of 39^ oz. of oil, or -86 per cent. 
As the oil contained impurities such as dirt and particles of bark, <fcc., it was strained first through 
a piece of calico and then through a filter paper, by which means I obtained a clear, light golden-coloured 
oil with a tinge of green, and possessing a delicious odour. 
The following chemical research on this oil was next undertaken by 7 Mr. Henry G. Smith, F.C.S., 
Chemist of this Museum. The oil obtained in the three distillations gave the following results, severally 
and when mixed together :— 
Specific gravity .— 
The oil of the first distillation = C0011 @ 16° C. 
,, second „ = T0012 ,, 
,, third „ = 1-0010 „ 
The whole oil obtained when mixed together had a, specific gravity of T00105 @ 16° C. 
These determinations were made with a delicate pycnometer holding about 12 grams. 
Specific rotation. —This was taken in a tube 200 mm. long ; using the sodium flame, the oils were 
found to be dextro-rotatory as follows :— 
First oil—angle observed + 223 therefore [a] D + 1T137. 
Second oil— „ + 22-2 „ [a] D + 11 080. 
Third oil—- „ + 22-0 „ [a]p+11-000. 
These were then mixed, when the rotation was + 22T, or a specific rotation [a]n + 1T038. All 
taken at 16° C. 
Redistillation .—100 c.c. of the oil were distilled at the ordinary atmospheric pressure with the 
following results. Only a few drops had been obtained at 185° C., the mercury then rapidly rose to 204° C.; 
between this and 213° C., 5 per cent, had been obtained :— 
Below 213° C.*. 
Between 213 and 217-2° C. . 
i 
First fraction collected -{ 
217-2 „ 221-4° C. . 
221 4 „ 224-6° C. . 
224-6 „ 226-7° C. . 
226-7 „ 229-8° C. . 
229-8 „ 235° C. . 
Second fraction 
Third fraction 
„ 235 „ 240-3° C. . 
„ 240-3 „ 245-6° C. . 
„ 245-6 „ 253° C. . 
Residue boiling above 253° C. . 
... 5 
= 7 
= 8 
= 7 
= 7 
= 7 
= 16 
= 17 
= 11 
= 10 
per cent. 
= 5 
Evidently better fractions could be obtained by changing at 230° C., as 54 per cent, distils between 
that temperature and 253° C. 
The fractions obtained as above gave the following results:—First fraction, between 213° C. and 
235° 0., had a specific gravity of -995 @ 16’ C., being thus lighter than water. It had a specific rotation of 
[a]o + 15-86, or half as much again as that obtained for the whole oil. 
These temperatures have been corrected to the nearest decimal. 
