blood, it cannot flow much more quickly than is natural with impunity. How often are boys seized with a pain in the region of the liver, after running with rapidity?

The calces of mercury do certainly give the utmost relief, both in acute and chronic hepatitis. While in the acute kind we employ between the tropics the antiphlogistic plan, blistering, blood letting, and especially purgatives, we ought not for a moment, if the disease is severe, to delay the use of the calces of mercury internally, with the ointment externally, as being of more consequence than all the other means in our power. No condition, to which human nature is exposed, is more deplorable than that where an abscess has taken place in the liver. I know of no sufficient security in that climate against such an evil but mercury. As soon as the mouth gets sufficiently affected, and the system is impregnated with it to a proper degree, the pain, the fever, and the distress abate, and the patient remains quite secure from the risk of abscess, provided we have not used the remedy too late, and when such a change has taken place as must necessarily end in abscess. While nobody is better acquainted with the inestimable benefits that arise from the due use of mercurials than myself, nobody can better know the ill consequences that follow them. In those predisposed to scrofula, they excite it; in those with a tendency to consumption, they accelerate it; and they have other bad consequences that I need not mention. When, however, we are threatened with the formation of matter in the liver, we must neglect all those considerations, and submit to smaller evils, in order to avoid one of the most melancholy kind.

When in India, I was most anxious to discover a substitute for the mercurial calces, less injurious and equally efficacious, and I have not been entirely without success. I knew that the nitric acid acts most readily on the resinous matter of the bile, and I was in hopes that I might communicate such an acidulous state to the living body as should produce the effects that I desired. That it may alter the nature of the urine has been proved by Mr. Brande, who has recommended the use of it in a particular kind of urinary calculus. If large secreting

glands are thus materially affected by merely drinking this acid, I cannot doubt but that by bathing the whole surface of the body below the head, in a very dilute nitric bath, much of it may be absorbed, and more material effects produced. I had found that through the medium of the stomach the effects of the acid, if given to the wished-for extent, might be injurious, and I had tried to little purpose to combine it with substances for which it has but a slight affinity, expecting by such combinations to diminish its action on the stomach without destroying its useful qualities. From its absorption by the skin, some effects have arisen that I think very important. We are destined to find our way by experience, and can never know to what an untried agent may lead us at last.

I gave, many years ago, a short account of my trials with the nitric acid in India. It was obtained there by means of alum from common crude Bengal saltpetre. In that country both alum and saltpetre are plentiful and cheap; but I could not obtain the sulphuric acid, unless from Europe, or by making it myself. In both cases it would have been expensive, from requiring either the payment of freight for a long voyage, or the expense of erecting a considerable apparatus. I was satisfied, therefore, with the acid procured, as I have said, from unrefined saltpetre and alum. I was aware that that acid was far from pure. I knew that it was mixed with a considerable proportion of muriatic acid, derived from the muriates which that saltpetre so plentifully contains. I had long given this acid internally, and I had found it harmless, and sometimes very useful. I was far from thinking at that time, nor did I suspect till long afterwards, that pure nitric acid is unequal to the production of all the benefits which I sometimes derived from my acid applied to the surface or to the stomach. A suspicion of this kind first arose from the circumstances that I must now explain, at the risk of being thought tedious. At that moment I lamented the impurity of my nitric acid, and I was sorry to use alum instead of sulphuric acid, although in the end both of those circumstances have been highly useful, by leading me to conclusions at which I never otherwise could have arrived.

At the Presidency of Bombay we have extensive works for gunpowder, from which the armies on that side of India, and occasionally the navy, are supplied with that material of war. The manufacture of this article had fallen into the hands of some Parsees, who, as in other cases, had some practical knowledge, but no kind of science, to direct them. Complaints of the gunpowder had become very general. It grew moist in the magazines, and did not, after keeping, answer to the common modes of proof. So very ignorant were those men, that they perpetually returned all the liquor remaining after the crystallizations of their saltpetre on the next quantity to be crystallized. They judged their saltpetre to be sufficiently pure and fit for gunpowder when they saw the crystals clear and transparent, and free from charcoal or mud. After a committee of intelligent officers had reported on this state of things, I was desired to take charge of those works, which I continued to hold till my departure from India. By adopting the necessary measures, our gunpowder soon became as good. as any in the world. One of those changes (and it is what leads me to the present digression) was the purification of the saltpetre. I had read in the “Annales de Chimie" a proposal of M. Lavoisier to purify that article for gunpowder, by reducing it to powder and then washing it with two portions of water. These two washings were sufficient to dissolve nearly the whole of the deliquescent salts, with a certain portion of the nitre. This to us was not only a very effectual operation, but it was one profitable to the public, for by evaporating the liquor of the two washings we recovered a quantity of saltpetre, impure indeed, but when mixed with charcoal, &c. still fit for making fireworks for the celebration of the weddings of the natives. As during the state of warfare which prevailed at that time, it was judged proper to prohibit the importation of saltpetre for sale, the product of our washings was gladly purchased. After saltpetre has thus been carefully washed, it is perhaps free enough from saline impurities to be fit for gunpowder; but I have always given it one subsequent crystallization, fearing it might contain a little sand or other matter, by which a spark and an explosion might be produced.

Being at that time impressed with a belief that the effects of my acid on the human body arose entirely from the nitric acid, I thought it would be a great improvement if I distilled it, not, as usual, from the crude saltpetre, but from such as had been washed in the way I have mentioned. This practice I continued for a long time, and indeed until I left India. Since using this purer saltpetre, I have often imagined that some of its beneficial effects were no longer produced, or were less remarkable. But my means of observation were cut short, first by very bad health, and then by being obliged to leave India for this country. Until lately I had no opportunity of seeing the sick here, or of recommending remedies for them; but still the suspicion of my having diminished the power of the acid, by purifying the nitre, hung on my mind, and I resolved to put it to the test of experience, as soon as I might have it in my power. About seven months ago I came to London, and by the aid of some intelligent friends I have been able to ascertain facts that I think interesting. I have found that the acid produces many effects in this climate as readily as it did in India. For the reasons just stated, I have used in all my late trials, not the nitric acid, but an acid composed of three parts of nitric and one of muriatic acid. With the result of these trials I have been sufficiently satisfied; nor have I had reason to think, that a constitution broken down by disease, by the use of powerful remedies, such as mercury, or by the long continued action of the poison of syphilis, receives less benefit in this climate from the acid treatment than I have derived from it in India.

I long ago said that I had removed syphilitic affections by the nitric acid (it was rather the nitro-muriatic), which ad resisted mercury long and judiciously applied. I had combined the external with the internal use of the acid, and I succeeded, in some of those cases at least, which have been called pseudosyphilitic. This state of syphilis is thought by some able and eminent men to be a new disease, and arising rather from the consequences of the remedy than from the poison of syphilis still existing in the constitution. I know well that an indiscreet, or even a large use of mercury, may give rise to

much evil; but I may be permitted to say, that no skill nor prudence in the application of that remedy will at all times prevent the occurrence of pseudosyphilis. In it I believe that the poison of syphilis still exists, remaining occasionally dormant, and becoming, from unknown causes, active and injurious, and exerting again all its specific effects. I think, however, that the cause of pseudosyphilis is a scrofulous habit, acted upon at once by the poison of mercury and the poison of syphilis, for to such a habit of body they are both poisons. We cannot destroy the syphilitic virus without calling into action the scrofula, to which there is a predisposition, so that on the patient is entailed a new disease not less afflictive than either of those from which it arises. It may perhaps be thought some confirmation of this opinion, that during the whole of my residence in India, where mercury is so commonly, so largely, and sometimes so injudiciously given for affections of the liver, I never knew a single instance of this new disease having arisen where syphilis was certainly out of the question. That this sort of syphilis is very common in this country, is evident from the inspection of many of our public hospitals, where patients are often seen, who for years together have been subjected to many courses of mercury, and a variety of useless or hurtful remedies. Even in our streets many sufferers in this way must attract the notice of every medical man. It is not enough to say, that the nostrums of quacks, and the treatment of empyrics, have produced such evils. I have observed, that cases do occasionally occur where the utmost skill of the present times is found to be quite ineffectual. I now earnestly recommend the nitro-muriatic acid bath for this disease, a means yet untried in this country. I see that the nitric acid is given internally by many practitioners in Great Britain, and occasionally, I am assured, with advantage. The knowledge of this would sufficiently reward me for all the trouble I have bestowed on the subject, and here I might rest satisfied; but I wish still further to advance the use and the utility of the remedy. Like the calces of mercury this bath affects the gums and the salivary glands, giving rise occasionally to a plentiful ptyalism. Though it reddens the VOL. VI.

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No. 24.