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definite is known about the quantities of resin -spirit imported in Ceylon, 
as in the custom's statistics resin-spiritis is included, along with a number 
of other oils, under the general designation of "oils, other". 
On this occasion "Schimmel's test"^) is blamed from various 
quarters as unreliable, it being said that pure oils occasionally do not 
pass the test, whilst other oils containing up to 15 per cent, petroleum 
make a clear solution with 80 per cent, alcohol. 
We will not in this place discuss in how far these statements are 
correct, but we wish to point out that the solubility- test alone has 
naturally but a limited value, and will always give only general data, 
but that in such tests the ready practicability is one of the chief advan- 
tages. It is naturally impossible in such cases to prevent an occasional 
passing of adulterated oils. However this may be, the fact that the 
detection of the recent adulteration is in the first place due to 
"Schimmel's test", speaks volumes. The value of this test is fully 
admitted also by experts, and its retention recommended. 
In addition to this, the specific gravity, and above all the geraniol 
and citronellal - content of the oil, are important factors. For this 
reason Parry and Bennett recommend to lay special value on these 
constants when examining citronella oil, and they give the following 
limits for Ceylon citronella oil, based on examinations of normal oils: 
d-^5 50 = 0,900 — 0,915; aj) = 0° to — 15°; total geraniol (geraniol 
and citronellal): above 58 per cent. 
^15,50 ^^^^^ ^^Vo distillate (at 20 to 40 mm pressure in vacuo), 
not below 0,858. 
nj)2oo of the first io^/q of the distillate (pressure as above) not below 1,4570. 
Solubility: the oil must pass "Schimmel's test". 
For the present we will leave it an open question in how far 
these requirements are justified, as we are expecting authentic samples 
from Ceylon, and numerous tests made by us with purposely adulterated 
citronella oils from Java led to a somewhat different result, and cannot 
therefore be included within the scope of these observations. We hope 
soon to be in possession of the material required for examination, and 
then to clear this matter up further. 
^) According to our method of testing citronella oil, known as "Schimmers 
test'*, the oil should make a clear solution with i to 2 vol. 80 ^/^ alcohol at 
20° C, which should remain clear even when 10 vol. alcohol of the same strength 
are added, or at most show a faint opalescence. Even after prolonged standing no 
drops of oil should separate from the solution. As regards the execution of the 
test we would point out, that turbid mixtures should only be shaken sparingly, as 
otherwise the oil becomes so finely suspended that insoluble parts only separate out 
after a very long time, which renders the observation more difficult. The time 
required for the observation should be about 1 2 hours, during which the temperature 
should be kept at about 20° C. 
