a Chinese drug, of which the composition will no doubt appear as singular as the numerous properties ascribed to it. In the province Chang-tong, near Ngo-hien, a city of the third class, is a well formed by nature, which is reckoned to be seventy feet in depth, and which has a communication, as the Chinese say, with some subterranean lake, or other large reservoir. The water drawn from it is exceedingly clear, and much heavier than common; and if it be mixed with muddy water, it purifies it and renders it limpid, by precipitating all its impurities to the bottom of the vessel. This water is employed in making the ngo-kia, which is nothing else but a kind of glue procured from the skin of a black ass.

The animal is killed and flayed, and the skin is steeped for five days in water drawn from this well. At the end of that time, it is taken out to be scraped and cleansed; it is afterwards cut into small pieces, which are boiled over a slow fire, in the same kind of water, until it is reduced to a jelly, which is strained, while warm, through a cloth, to free it from all the gross matter which could not be melted. When this glue is cool, and has acquired a consistence, it is formed into square cakes, upon which the Chinese imprint characters and coats of arms, or the signs of their shops.

This well is the only one of the kind in China; it is always shut, and sealed by the governor of the place with his own seal, until the customary day of making the emperor's glue. This operation generally lasts from the autumnal harvest till the month of March. During that time, the neighbouring people and merchants treat for the purchase of the glue with those who guard the well, and with the people who make it. The latter manufacture as much of it as they can, on their own account, with this difference, that it is not so pure, and that they are less scrupulous in examining whether the ass be fat, or of a very black colour: however, all the glue made here is as much esteemed at Peking as that which the mandarins who are on the spot transmit to court and to their friends.

As this drug is in the greatest request, and as the quantity of it made at Ngo-hien is not sufficient to supply Ngo-kia, supply the whole empire, there are not wanting people who counterfeit it elsewhere, and who manufacture a spurious kind from the skins of mules, horses, and camels, and sometimes even from old boots; it is, however, very easy to distinguish that which is genuine; it has neither a bad smell nor a disagreeable taste when applied to the mouth; it is brittle and friable, and always of a deep black colour, sometimes inclining to red. The qualities of the counterfeit kind are entirely different; both its taste and smell are disagreeable, and it is viscous and flabby even when made of the skin of a hog, which is that which imitates the true kind the best.

The Chinese attribute a great number of virtues to this drug. They assure us that it dissolves phlegm, facilitates the play and elasticity of the lungs, gives a free respiration to those who breathe with difficulty; that it comforts the breast, increases the blood, stops dysenteries, provokes urine, and strengthens children in the womb. Without warranting the truth of all these properties, it appears, at least, certain, by the testimony of the missionaries, that this drug is serviceable in all diseases of the lungs. It is taken with a decoction of simples, and sometimes in powder, but very seldom.