VARIETIES. 
377 
Preparation of Oily Emulsions. — The preparation of oily emulsions suc- 
ceeds better, according to Overbeck, if the following proportions of gum be 
employed: — Different oils conduct themselves differently when rubbed 
down with gum- castor oil differing most in this respect from the other 
oils. In order to obtain a perfectly milk-white emulsion of castor oil, two 
drachms of gum are to be mixed with three drachms of water and one 
ounce of castor oil, which is to be poured, by a fine stream, into the con- 
stantly stirred mucilage. Any additional quantity of water is then readily 
taken up by the emulsion, which may also be prepared with only four scru- 
ples of gum, but without becoming quite white. For other oils half their 
weight of gum is required, and the quantity of water must be half the total 
weight of oil and gum. Thus one ounce of oil of almonds is to be first rubbed 
down with half an ounce of gum, and six drachms of water are then to be 
added at once. The so-called crackling [Krackeii] of the emulsion appears 
here in a higher degree than after the usual method, and is a favorable 
symptom of the uniform distribution of the oil in the water. — Lon. Pharm. 
Jour. July, 1851, from Central Blatt, 1851, No. vi., p. 75. 
Adulteration of the Oils of Lavender and Cassia. — Br. Hartung Schwarz- 
kopf obtained from a commercial house, which he does not in the least sus- 
pect of participating in the fraud, the oils of lavender and cassia, as being 
of the finest quality ; the first of which does not at all possess the pure, 
agreeable perfume, but an accessory odor of turpentine and rosemary. 
This odor became more distinct when the oil was poured upon a cloth and 
moved about in the air, or when it was heated in a spoon. Iodine gave no 
trustworthy indications; but the adulteration with oil of turpentine was 
readily discovered when the oil was shaken with three times its quantity of 
alcohol of 0.83 p. weight, which was incapable of dissolving the oil. The 
presence of oil of rosemary could not be discovered by this test, since this 
oil dissolves in alcohol of the above strength. The oil of cassia possessed 
the pure odor of cassia, but was suspicious by its great liquidity. The usual 
tests for adulteration with spirits of wine gave no satisfactory results. 
Upon mixing the oil with water it did not become opaque, and a drop of 
the oil being allowed to fall into a glass filled with water produced no 
opaque streak. Perfectly dry calcium being thrown into the oil dissolved, 
and formed under the oil a liquid layer, which satisfactorily proved the 
presence of spirit of wine. — Ibid, from Central-Blatt, 1851, No. iv., p. 62. 
Bleaching of Ivory by Sidphuric Acid. — Ivory knife-handles, which have 
become quite yellow from use, being left for from two to four hours in a 
watery solution of sulphurous acid, become white again. The acid in the 
gaseous form makes the ivory crack. — Ibid from Ibid. 
On Bebeerine. By M. A. De Planta. — An organic base has been known 
in commerce for some time past, which was obtained in 1834 by M. Kodie, 
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