cipient and milder state, from its general prevalence, was not recognised either by the other practitioners of the town where I then resided, or myself, to be the genuine painters' colic.

This town, a sea-port in Essex, contained between three and four thousand inhabitants, and at the time I speak of, very many people, chiefly adults, and a greater proportion of them men, complained of occasional violent colic pains, chiefly occurring after meals, attended with an obstinate costiveness; and although these symptoms were for a time relieved by the use of purgatives and other means, they almost universally recurred. The progress of the disease, even in those cases where it attained its utmost violence, was in almost every instance so insidious and so slow, as to leave us unapprehensive of its true character; which, however, was at length brought to light in the following

manner:

An infant, under twelve months, at the breast, who had been subject to complaints arising from acidity of the food, was tormented with most excruciating pain, apparently in the bowels, attended by a very great degree of constipation, and accompanied with violent straining efforts at evacuation, resembling tenesmus. The sufferings of this poor little child were in the highest degree distressing, and it obtained but temporary relief from the warm bath, laxative injections, those of an anodyne quality, the throwing up into the rectum warm oil, opiates and purgatives combined, or from any treatment whatever that could be suggested. The seeing so unusually severe a case, suggested to my mind the probability that some improper substances had been exhibited to the little patient, and I was earnest in my inquiries to this point. All my endeavours only ascertained that the nurse had occasionally given the child a tea spoonful or two of ardent spirit in its food; a practice, which, although I much reprobated, I knew to be too common among nurses, solely to account for this violent disease. My patient at length fell a victim; and a very short time after, the father of the child regretting to me the mismanagement of its nurse in giving it spirits, observed, that he himself was occasionally tormented with pains in hist bowels, which he was inclined to attribute to drinking a single glass of Hollands and water every night. This induced a suspicion in my mind; and upon dropping into a small quantity of the spirits a single drop of the volatile incture of sulphur of the old London Pharmacopoeia, it assumed a very dark colour, affording a certain evidence of

its containing a metallic poison. This Hollands geneva had been bought at the king's excise warehouse in the town, where many hundred gallons were annually sold, that had been seized by the excise officers from persons attempting to smuggle it into this country. The gentleman, grieved at the loss of his child, which he could no longer fail to attribute to its true source, brought up the chief managing officer before the magistrates; when he confessed that the whole of the quantity of Hollands sold at the last sale had been impregnated with sugar of lead, for the purpose of depriving the spirit of the colour which it always obtained by being kept for some time in the tubs in which it was brought over sea by the smugglers, and the loss of whichcolour enhanced its price by three or four shillings a gallon. This circumstance afforded an easy explication of the cause of the malady which had so generally prevailed; and henceforth none other than coloured Hollands were exposed to sale at the excise warehouse, as had been the custom previous to this scientific attempt of the above officer, at once to increase the king's revenue and his own.

This recital strongly illustrates the obscurity in which the occasional causes of disease may sometimes be involved; and, as a proof of the difficulty of raising suspicion of the deleterious quality of substances, I may mention, that among those who died on this occasion was a dissenting clergyman, about sixty years of age, a man of good sense and observation, of temperate habits (if the daily custom of taking a glass of spirits and water after supper is not to be considered a deviation from the rules of temperance), whose wife carried on the business of a druggist; and it may be supposed they were both acquainted with the noxious qualities of the preparations of lead: yet it appeared that the sugar of lead with which this spirit was impregnated had been bought at their house by the exciseman himself, and in quantities of 28lbs. at a time; but it did not occur to either of them, or to his medical attendant, that the disorder was connected with the drinking of the Hollands. It is to be remembered, that in the early stages we have no certain diagnostic signs by which the colica pictonum can be distinguished from the other species of colic; it is only by its ultimate effects, or by a knowledge, of its exciting causes, that we can confidently pronounce concerning the existence of the disease.

W. SHEARMAN.

XXII. Memoir on the Existence of a Combination of Tannin and a vegetable Matter in some Vegetables. By Messrs. FOURCROY and VAUQUELIN*.

§ I. Subject of our Inquiries.

Ir was natural to suppose that when there were formed, either successively or simultaneously, tannin and animal substances in vegetables, these two compounds would unite when they met: nevertheless, although the knowledge we have acquired on the subject of tannin and the animal substance give great probability to this opinion, no chemist has yet announced the existence of this species of combination in plants.

Upon analysing several vegetable matters more or less different from each other, and particularly the Indian chesnut, garden beans, lentils, &c., we discovered the compound in question, and we shall now give the result of our experiments.

The facts which we are about to describe seem interesting, because they afford an explanation of a great number of phænomena observed in the analysis of vegetables, as well as in their employment in dyeing or in other arts,phænomena which the chemists have not yet been able to account for.

§ II. Examination of the Skin of Garden Beans.

It was in the skin which covers the cotyledon of the bean that we first ascertained the combination of tannin with an animal matter.

When macerated in tepid water for 24 hours, this tunic communicated to the water the property of reddening turnsole tincture, that of precipitating the solution of sulphate of iron blue, the solution of glue in yellowish-white, lime water in red flakes like oxide of iron, the acetate of lead in yellowish-white, and at the same time the property of experiencing no effect from the infusion of gall-nuts.

The characters of this water prove that it contains a free acid and tannin. We must here remark, that pure tannin precipitates iron brown, and that when it is joined with an acid it precipitates it blue.

The skins of garden beans submitted four different times to the action of large quantities of boiling water always communicated to it the above properties, but in a remarkably decreasing ratio.

*Ansies du Museum d'Hist. Nat. tome xv. p.

When

When they no longer furnish any thing to the water, they preserve the property of becoming instantly of a deep black by the application of a little sulphate of iron: even when reduced to pulp and washed with boiling water, they still become black when in contact with this salt.

§ III. First Result of the foregoing Trials: ulterior Experiments on the same Bodies.

These experiments began to make us suspect that the tannin to which the effects above described are manifestly owing, was combined in the pellicles of the garden beans with some substance which opposed its solubility in water.

In order to ascertain, if possible, the nature of this substance, we put into a slight solution of potash a portion of pounded pellicles, and heated the mixture gently. The liquor soon became of a purple-red colour, as well as the substance of the pellicles. When filtered, and mixed to saturation with the acetic acid, this liquor precipitated a reddish matter in the form of flakes, having a gelatinous appearance; and it preserved but a very feeble colour itself.

The alkaline lixivium, thus cleared by the acetic acid of the substance which it had taken up from the pellicles of garden beans, did not give a blue colour to the solution of sulphate of iron; the mixture merely assumed a slight brownish colour; but the matter precipitated, on the contrary, became intensely black with this metallic solution, so that the tannin was really dissolved by the potash with the matter to which it was united, and afterwards precipitated with this same substance by the acetic acid, the action of which is here confined to the saturation of the potash. The pellicles of the beans, when cleansed by repeated washings, and distilled in a slow fire, furnished a liquor slightly acid, but from which caustic potash extricated a great quantity of ammonia: the produce of the distillation, before being thus mixed with the potash, gave a blue precipitate with sulphate

of iron.

From these last experiments, it appears no longer doubtful to us, that the skins of garden beans actually contain a combination of tannin and an animal substance: we are even inclined to think that the greatest part of the parenchyme of those skins is formed of this combination.

Their charcoal yielded upon incineration a small quantity of ashes formed of carbonate of lime, phosphate with the same base, and oxidated iron.

The envelopes of the lentils presented precisely the same properties

G 3

properties and the same results with those of garden beans: we shall therefore dispense with any further details on this head.

§ IV. Examination of the Leaves of the Indian Chesnut-tree.

The leaves of the chesnut-tree, when deprived by alcohol of all which was soluble in it, having been afterwards subjected to the action of boiling water, communicated to it a light-brown colour, viscosity, and the property of frothing on agitation.

This liquor, when evaporated to dryness, left a small quantity of brownish matter, which was attached to the capsule in a thin shining layer like a gum, which burned with a crackling noise, exhaling a fetid vapour sensibly ammoniacal. Its solution in water precipitated iron black, and the acctate of lead yellow, but produced no effect in glue, nor in the infusion of gall-nuts.

We are of opinion that this substance is also a combination of animal matter and of tannin insoluble in alcohol, and by no means a gum, as the appearances denote; and this combination, as is the case with the pellicles of garden beans and lentils, is accompanied by a superabundance of tannin, which alcohol takes up. Thus, when we treat these substances directly by water, the free acid and tannin favour the solubility of those combinations saturated with the animal matter and tannin, which for the greater part remain insoluble, in the case in which we first treat these vegetable matters with alcohol.

The leaves of the chesnut-tree, when successively freed by alcohol and by water of every thing which is soluble in these two menstrua, and when dried and afterwards distilled, furnished an ammoniacal vapour so strong as to be scarcely supportable, and a very alkaline liquor. This last, when saturated by the muriatic acid, precipitated the solution of sulphate of iron in blackish blue; which proves that there still remained in these leaves a certain quantity of the combination of animal matter and tannin, which neither the alcohol nor the water could dissolve.

V. Attempts made to imitate the vegetable Compound above described.

Although we were well convinced, by the properties which we have detailed, and by various other experiments on the leaves of the chesnut-trec, that the matter in question is a true combination of animal principle and tannin,

we