M. Cadet, in addition to many of the above characteristics of Myrtle wax, found that it combined readily with the semivitreous oxyde of lead, forming a very hard plaister. When distilled in a retort, the wax was partly decomposed, and a portion which passed over was white and of a soft consistence. Oxygenated muriatic acid bleaches it, but with more difficulty than bees

wax.

The experiments which I have made on this substance confirm the preceding statements with the following exceptions. Cold alcohol dissolves a minute portion, which is gradually separated by the addition of water, and floats in perceptible flocci, near the surface. Cold ether dissolves about one sixteenth of its weight. This it does with great rapidity, and if thin shavings of the wax be dropped into a vessel of ether, they disappear almost immediately.

Dr. J. F. Dana has published, in Silliman's Journal, an account of some experiments made to ascertain the proportion of wax, and of the other parts which compose the entire berry. He found the wax to constitute nearly a third of the whole, or thirty two per cent; the kernels 47.00, the black powder 15.00, with about 5.00 of a resino-extractive matter.

This

There undoubtedly exists, in the berries of this shrub, some interesting constituents beside the wax and insoluble portions, as the following results will show. If water be distilled from the fresh berries, it acquires a slight pearly appearance and a fine aromatic odour and taste. indicates the presence of a volatile oil, though I have not performed the experiment sufficiently in the large way to obtain any oil separate. The decoction remaining in the retort gives proofs of gallic acid.

When the wax, in a separate state, is boiled in alcohol, a portion is dissolved, which is mostly deposited on cooling, leaving the fluid clear. But if alcohol be boiled upon the berries till a strong solution is formed, it does not give a deposit on cooling, but the solution coagulates into a soft solid and remains afterwards unaltered. This coagulum is readily soluble in cold ether, and melts when exposed to heat. If the berries be boiled in water until the wax is melted and principally detached, the remaining parts still give a coagulating solution with alcohol.-The tincture made by digesting cold alcohol on the bruised berries is considerably coloured, and becomes turbid on the addition of water, but whether the resinous substance thus precipitated

is the same in small quantity, which produces the coagulation in a large one; I am not prepared to say.

It appears, then, that there exists in the berries of the Myrica a peculiar vegetable principle, bearing nearly the same relation to alcohol, as starch and gelatin do to water. I have not yet obtained it in a separate state, and cannot therefore give any additional characteristics to those which have been already stated.

The Myrtle wax is useful for many of the purposes for which bees wax and tallow are employed, particularly for candles. It burns with a clear flame, though less vivid than that of common oil, and emits a considerable fragrance. It was formerly much in demand as an ingredient in a species of blacking ball, to which it communicated a temporary lustre and power of repelling water. It has occasionally been used in pharmacy in various compositions intended for external use, and is mild or stimulating according as it is more or less pure and freed from the colouring matter.

In some parts of Europe plantations of this shrub have been raised with a view to the profit to be derived from the wax. In this country, where the shrub abounds, the berries are often

neglected, their collection and the separation of the wax being deemed too laborious to compensate the trouble.

In Dr. Thatcher's Dispensatory, we are informed, on the authority of Dr. Mann, that the bark of the root of the Myrica cerifera is emetic. With a view to examining thoroughly its medicinal properties, Dr. S. L. Dana, in 1818, made it the subject of an inaugural dissertation. He found that the powdered bark was acrid and astringent, but did not appear to possess any other qualities than were attributable to those two. Moderate doses of the powder and decoction produced no effect on the stomach or bowels. Large doses, for instance two scruples, were swallowed with difficulty on account of their acrimony, and occasioned heat and nausea at the stomach. Larger doses, of a drachm, produced a powerful burning sensation and vomiting. Costiveness generally followed the use of this medicine. The powder, when snuffed up the nose, proved pow. erfully sternutatory, and when applied to the fungous granulations of an ulcerated leg, it produced so much pain as compelled the patient to wash it off.

We may then consider the bark of the Myrica as an acrid stimulant and astringent. That it

sometimes proves emetic, in large doses, is to be explained in the same way as the operation of mustard and horse-radish, which some of the older physicians employed as emetics. When the stomach is burdened with an undue quantity of stimulus, it naturally tends to relieve itself by vomiting.

On the whole, we are to esteem the Myrica cerifera as more interesting in a chemical, than a medical point of view. The pleasant aroma of the water distilled from the berries, and the application of the wax to some purposes of pharmacy, are all, that this shrub at present offers, much deserving the attention of physicians.

BOTANICAL REFERENCES.

Myrica cerifera, WILLD. iv. 745.-MICHAUX, ii. 227.-PURSH, ii. 620.-Myrtus foliis lanceolatis, &c.-GRONOVIUS, 155.-Myrtus brabanticæ similis, &c.-CATESBY, i. 13?

MEDICAL AND CHEMICAL REFERENCES.

CADET, translated in Nicholson's Journal, 8vo. vol. iv. 187.BOSTOCK, in ditto, 129.-KALM, Travels, i, 129.-DANA, in Silliman's Journal, vol. i.-THACHER, Disp. 288.