NOTE ON THE DIVISION OF GUM RESINS IN POTIONS, AND IN DIACHYLON PLAISTER.
At a recent meeting of the Society of Pharmacy, M. Poulenc, submitted a method which he has employed for eight years in his laboratory, for suspending gum resins in medical prescriptions. It is well known how much difficulty there is in suspending either in a mixture, or lotion, one or more grammes of gum ammoniac, assafœtida, myrrh, &c. In dividing the {59} assafœtida with yolk of egg alone, the manipulation is long; but if instead of the egg, we employ 6 or 8 drops of oil of sweet almonds per gramme, the gum resin, even when entire, is easily reduced; when the oil is well mixed, and the paste as homogeneous as possible, a little water is first added, then gradually the quantity of the prescribed vehicle, as for the mucilage of a linctus; the product of this operation will be a speedy and very perfect emulsion. One of the advantages of this modus faciendi, is, that the product can be warmed without danger of coagulation, besides which, it is generally more easy to obtain a few drops of oil of sweet almonds, or any other kind of oil than the yolk of an egg.
M. Poulenc has recently applied the same method to the manufacture of diachylon plaister, in the following manner: take some entire pieces of gum resin, and triturate them briskly in an iron mortar, after which in a marble, or porcelain mortar, mix in the oil, and add a sufficient quantity of water to obtain an emulsion about as thick as liquid honey; strain this through a coarse cloth; there will be hardly anything left on the cloth, and the strained substance will be perfectly homogeneous. Evaporate in an earthen vessel, by the water-bath, the water which had been mixed in, and when the mass presents the appearance of a soft extract, the other ingredients of the plaister may be mixed in with the greatest ease. This plaister presents a very beautiful appearance, and exhales a very decided odour of the gum resins employed in its composition. Should it be feared that the small quantity of oil, might weaken the consistence of the plaister, M. Poulenc thinks that the quantity of turpentine might, without inconvenience, be slightly diminished.
We have tried with success the method of M. Poulenc for emulsions with gum resins; as to its further use in the preparation of diachylon plaister, we cannot speak with certainty.—There is a chemical question, which, in all cases governs the preparation of pharmaceutical agents.—Stan. Martin, L’Abeille Medicale.
{60}
ESSENCE OF JARGONELLE PEAR. BY THE EDITOR OF THE PHARMACEUTICAL JOURNAL.
The liquid sold under this name, and which has been for some time in use by confectioners, is the acetate of the oxide of amyle.
It is prepared with great facility by submitting to distillation a mixture of one part of amylic alcohol (better known by the name of oil of grain,) two parts of acetate of potash, and one part of oil of vitriol. The distilled liquid is to be washed with alkaline water, dehydrated by chloride of calcium, and afterwards rectified by distillation from protoxide of lead.
Its properties are thus stated by Dumas:—In the state of purity it is a colorless, very limpid, volatile liquor, which boils at 257° F. It possesses an ethereal aromatic odor, somewhat resembling acetic ether; its sp. gr. is less than that of water. It is insoluble in water, but soluble in alcohol, ether, oil of grain, &c. Concentrated sulphuric acid does not color it in the cold; but by heating the mixture, it becomes reddish-yellow, and when the temperature is elevated, destructive reaction takes place, the mixture blackens and evolves sulphurous acid. Placed in contact with a watery solution of potash it is very slowly altered; but an alcoholic solution of this base rapidly decomposes, an alkaline acetate is formed, and the oil of grain regenerated. Its ultimate composition is
| 14 equivalents of carbon, | 84 |
| 14 equivalents of hydrogen, | 14 |
| 4 equivalents of oxygen, | 32 |
| 130 |
But its proximate composition is amyle, (an hypothetical radical) oxygen, and acetic acid.
| 1 equivalent amyle (C10 H11) | 71 |
| 1 equivalent oxygen, | 8 |
| 1 equivalent acetic acid, (C4 H3 O3) | 51 |
| 130 |
Its formula is thus stated by Brande, AylO, AcO3; by Fownes, AylO, C4 H3 O3.
Amylic alcohol, or oil of grain, called by the Germans fuselol; is the hydrated oxide of amyle, AylO, HO. It is {61} largely produced in the distillation of spirit from corn. It is officinal in the Dublin Pharmacopœia, where it is termed “Alcohol amylicum—Fusel oil,” and is employed to yield valerianic acid in the process for making “Sodæ Valerianas.”
From information which we have received, we have reason to believe that the use, by very young children, of articles of confectionery, flavored with essence of pear, is not without danger. A child on two occasions became partially comatose, with livid lips and feeble pulse, after eating some confectionery which it was calculated contained about one drop of the essence.—London Pharmaceutical Journal, November, ’51.
On the Growth of Plants in Various Gases, Especially substituting Carbonic Oxide, Hydrogen, and light Carburetted Hydrogen for the Nitrogen of the Air.
{62}