In comparing the remedial efficacy of alum with that of the vegetable astringents, it will probably be found to be relatively more efficacious, when operating through the medium of the circulation, than directly upon the stomach and bowels. It is, indeed, sometimes given very advantageously in Menorrhagia or uterine hemorrhage, and in cases of bloody urine. In obstinate haematuria connected with disease of the kidneys, I have known it apparently to produce the happiest results, after vain trials of other methods. There would seem to be no reason why it should not also prove serviceable in haemoptysis; but it is less used in that affection; and I have myself so seldom employed it, that I should not be justified in giving an opinion, upon the ground of experience.

In all the above affections, alum may be used in combination with small doses of opium, which generally co-operates to the same result, and may also serve to obviate, in some measure, its tendency to irritate the stomach. For the latter purpose, one of the aromatics is also not unfrequently conjoined with it, as nutmeg or cinnamon, especially when it is given in powder.

With reference to its astringent property, alum has also been given in dilatation of the heart, and aneurism of the aorta, and sometimes, it has been thought, with advantage. Incontinence of urine from debility of the sphincter muscle of the bladder, spermatorrhoea, obstinate leucor-rhoea, colliquative sweating, and diuresis, are other complaints in which it has been used with supposed benefit, and in which it would seem to be indicated. Little good can be expected from it in proper diabetes, in which it has, nevertheless, been recommended.

It was formerly supposed to possess febrifuge properties; and Cullen states that he succeeded with it in intermittent fever, given in connection with nutmeg, in anticipation of the paroxysm. But it is not to be relied on, and is not now employed in that disease.

Of much greater importance is it as a remedy in colica pictonum or lead colic. So long ago as the middle of the last century, it was employed in that affection by Grashius, a physician of Holland, and afterwards by Dr. Thomas Percival of England; but it did not attract particular attention until, at a comparatively recent period, it was brought into notice by M. Kapeler, physician to one of the hospitals of Paris. Since that time, it has been extensively used, and experience has pronounced decidedly in its favour. I have myself employed it with the best results, even where the opiate and mercurial treatment had failed. Its mode of operating is quite unknown. Some suppose that it cures the disease by converting the poisonous preparation of lead, which may have caused it, into the insoluble and inert sulphate of that metal. But it is by no means always that lead-colic proceeds from a preparation of that metal swallowed. Quite as often, probably, it originates through the inhalation of the fumes of the metal, or of vapours impregnated with one of its salts; and there is in such cases no poison in the bowels to neutralize. Besides, even when the poison has been swallowed, it probably acts much more through absorption into the blood than by mere contact with the membrane. If alum, therefore, act merely as a chemical antidote, it must do so by entering into the circulation, and there producing the insoluble sulphate, which, in this position, would probably produce as much mischief mechanically as the poison had done physiologically. But, independently of these considerations, it is a sufficient refutation of the notion of the chemical action of alum, that the same curative effect is not obtained from Epsom or Glauber's salt, or other soluble sulphate, or from sulphuric acid itself, which ought to be equally efficacious, if the chemical theory were true. All that we can say on the subject, in the present state of our knowledge, is that, though alum and lead are both astringent, yet each has its own specific or peculiar mode of action, and that the influence of the former is incompatible with that of the latter; in other words, alum cures the poison of lead on the principle, already sufficiently discussed, of supersession. (See page 51).

The remedy is asserted to have been found effectual in other forms of colic; and it may be employed, with hope of special benefit, in those cases of intestinal neuralgia which are occasionally met with, bearing a close resemblance in their symptoms to colica pictonum. In this disease, alum is given in doses larger than are thought appropriate to most other cases in which it is used. From a scruple to a drachm or more may be administered every three or four hours, dissolved in some mucilaginous liquid, to which sulphate of morphia may be very advantageously added, in such quantities as may be necessary to allay the sufferings of the patient.

Alum has been recommended in hooping-cough by Dr. Davies, editor of Underwood's treatise on the diseases of children.

As an emetic, it has been advantageously employed in the treatment of pseudomembranous croup, by the two Drs. Meigs, father and son, of Philadelphia. A teaspoonful of the powdered salt is given to the child every ten or fifteen minutes until it vomits. A second dose is seldom required to produce the effect.

But it is topically that alum is most used. In arresting morbid discharges, it is among the most effectual of the local remedies in our possession. Epistaxis very rarely fails to yield to a solution of the salt, containing fifteen or twenty grains to the fluidounce, injected up the nostril. When the bleeding proceeds from a readily accessible part of the membrane, the solution may be applied by means of a piece of lint. In peculiarly obstinate cases, it has been recommended to snuff or blow up the powder; but the method is I believe less effective, as the remedy cannot be in this manner so thoroughly applied to the whole surface.

The same solution is scarcely less effectual in the hemorrhoidal flux, and in hemorrhage proceeding from a point higher up the rectum. Three or four fluidounces of it should be injected at once, along with two or three fluidrachms of the solution of sulphate of morphia, of the U. S. Pharmacopoeia.