tion; but there may be others still more efficacious which time will discover.

Although I had reason in India to be satisfied with the general effects derived from this acid, yet considerable inconvenience attended its internal use. If it were not given with great caution, it injured the enamel of the teeth, though not their roots, as mercury does. Even in small quantities, it disagreed with some stomachs, and few individuals indeed could continue it sufficiently long, or in sufficient quantity, to remove from the system the symptoms of secondary syphilis. These difficulties made me anxious to ascertain whether or not the acid, externally applied, would produce good effects. I accordingly employed it in this manner in various cases, and I immersed my own body up to the chin in a bath of this acid, sufficiently diluted with water. I fortunately have preserved the memoranda that I made at the time, of which the following is a copy.

Bombay 27th April, 1798.—I bathed to-day in an acid bath, which was merely acidulous. It covered the whole body below the head. I staid in it for half an hour, and it was nearly of the tem perature of the body. I feel no particular effect from this bath: it is fully as pleasant as water, and cleanses the skin like a soap.

"April 28. I bathed again to-day, keeping the bath at the same temperature, or making it rather higher, of the same strength with regard to acid. I staid in it half an hour. I still feel no material effect from the bath. Pulse after bathing 76°. The only apparent action of the acid is on such animal matters as are unprotected by life, with which it forms an acid soap. Would it not deprive feathers of their oily smell?

1

"29th. Bathed again, and continued, as before, for half an hour in the bath. To-day the bath was hardly so hot as the body. About half an hour after bathing yesterday, I became sensible of an odd sensation about my gums, my jaws, and my teeth.

"30th. Bathed again, and stayed half an hour in the bath. It was rather warmer than my body. Since yesterday I have been sensible of some uneasiness in my throat on swallowing. I feel a disposition to salivation at times, but I am otherwise well. My gums, both above and below, are somewhat reddened. I was for some time disposed to ascribe these effects to imagination, but they have continued all this day, and leave me no doubt of their reality. I am in good health.

"May 1st. Since yesterday I have felt some pain in my throat, especially on swallowing. This pain seems to follow the course of the œsophagus. During the whole of this forenoon I had a sense of burning over the roof of my mouth and down the gullet. This sensation is like what arises from having chewed an acrid vegetable substance, and is so unpleasant, that, unless it leave me by tomorrow, I shall bathe no more. To-day I bathed as usual, staying in the bath for half an hour. It has been to-day, and, in general, so acid, as to make my skin smart a good deal in many places.

"2d. My mouth, &c. though not in the least ulcerated, is some

what

what pained. I am sufficiently convinced of the great power of this bath, and shall bathe no more. My digestion is improved, and I feel that my liver, unclogged by disease, is doing its office with facility, which for some time past has not been the case with me.

"6th. I have not bathed again, but I still feel the effects of the bath in my mouth. My appetite is now good, and I sleep with tranquillity, which I had not done of late. With all this, my pulse is quicker than usual, and I am sensible of some degree of languor. It is, however, to be observed, that the weather is very hot; the thermometer being, during the day, in the shade, from 92 to 96 degrees of Fahrenheit.

In order to get a delicate test for acidity or alkalescency, I have been accustomed to rub the red petals of the hibiscus rosa sinensis on white paper, where they leave a blue-coloured stain. I observe when under the influence of the bath, the urine no longer turns this colour red, but destroys it altogether.

"June 6th. For a fortnight after giving up the bath, I was sensible of some of its effects about my mouth, and my pulse remained too quick. I am now remarkably well. My liver seems to be sound, and I have experienced a happier change than I ever did from mercury."

After this I used the nitro-muriatic bath in a variety of cases, and often with agreeable results. I now wrote another letter, giving an account of its powers: this letter was published in London, but it attracted very little attention, being tried. by few individuals. When I came to London, and had it in my power to have the nitromuriatic bath employed for various states of diseases, I was, as may be supposed, very anxious to know if it could be as commonly ap plicable in this climate as it is within the tropics. I have been much pleased to discover that it gives here the very same results that I formerly derived from it; nor are the maladies for which it may bring relief, less general in this country than in India. On the contrary, they seem to be still more abundant.

The acid that I have used of late is the nitro-muriatic; and it is formed by mixing together equal parts of the nitrous, or nitric acid, and muriatic acid, If these acids be in the state of concentration that they usually possess in the shops, and if the quantities be considerable, a great volume of gas is evolved on their coming into contact, which taints every part of a house, is extremely hurtful to the lungs, and disagreeable to the smell. To avoid all this inconvenience, I put a quantity of water, at least equal in bulk to both the acids, into a bottle, and I add the acids to it separately. This method does not only prevent the unpleasant odour, but it tends to retain the chlorine, on which its effects depend. It is well known that the nitro-muriatic acid acts very readily on the metals and earth; nothing therefore but glass, or extremely well-glazed ves sels of porcelain, should be used to contain it. Wooden tubs for bathing answer very well, and they should always be made as small as possible, compatibly with their holding the body, or the limbs. that we wish to expose to the bath. From their being small we

In India I have

save acid, and are able to heat the bath with ease. often exposed the whole body below the head to this bath; but here I have been satisfied in general by keeping the legs and feet exposed to it. In order to warm the baths after the first time, I have commonly made a third or a fourth part of it be thrown away, and the loss replaced by boiling water, and a proportional quantity of acid. To save the expenditure of acid, I have occasionally warmed a portion of the bath in porcelain vessels placed near the fire, but I fear this may diminish its effects.

It is no easy matter to give directions with regard to the degree of acidity of the bath. I have commonly made it about as strong as very weak vinegar, trusting to the taste alone. The strength should be regulated by the degree of irritability of the patient's skin. I may say, that, although I like to know that it is strong enough to prick the skin a very little, after being exposed to it from fifteen to thirty minutes, yet I believe that even such an effect as this is unnecessary.

The time, too, of remaining in the bath, in order to produce the greatest effect, is a matter of doubt; I have kept the legs and feet exposed to it for half an hour or more; but with more delicate people not above one-half, or one-third of that time. I have repeated these baths daily, or even twice or thrice a-day.

I must now observe that the mere sponging the skin with nitromuriatic acid, sufficiently diluted with water, gives rise to the very same effects with bathing, and is more easily applied. Fifteen or twenty minutes may be employed in the sponging, though I have found that a much less time does produce very material effects. When the bathing or sponging is carried to a considerable extent, and when the system is much under its influence, a sense of weakness comes on occasionally, some nervous irritation and restlessness are felt, a taste of metal (generally compared to that of copper) becomes sensible; a sense of pain occurs in some part of the palate or mouth, which is not permanent, but comes and soon goes off again. At length little specks or small ulcerations, extending no deeper than the cuticle, are seen on the interior surface of the mouth, and over the tongue, so that some degree of excoriation or rawness is at last produced. This is attended by a considerable discharge of saliva, with an increase of the feeling or lowness of depression. These effects resemble those of mercury, but they are not the same. The excoriation from the nitro-muriatic acid never reaches deeper than the cuticle: it never gives rise to fœtid ulceration of any kind; nor does it produce the least offensive smell of the breath nor in the mouth. The effects of it in this way are surprisingly fugitive. At one hour the discharge of saliva may be excessive; the next it will stop, and perhaps suddenly come on again. The excoriations in the mouth generally go away in a day or two, if the remedy be discontinued, and appear no more. While the mouth in this way is affected by the acid, the teeth partake of uneasiness; but I never saw this in a considerable degree, nor have I known any injury done to the teeth or their sockets. These lastmentioned

mentioned effects are seldom met with to the extent that I have described, and need not be excited unless some peculiar circumstances require an unusual power, such as the symptoms of syphilis. I have lately added more and more of the muriatic acid in proportion to the nitric, and the effects have proportionally increased. I now make use of equal parts of the acids. Would not the greatest power of the remedy be obtained by those proportions that produce the greatest quantity of chlorine; for from that element I believe all its effects arise? I am yet ignorant what effects would be produced by the muriatic acid alone.*

The nitro-muriatic acid appears in a particular manner to affect the glands, and to alter their secretions; and on this power a great part of its value in derangements of the liver seems to depend. It sometimes very suddenly increases the secretion of bile; and this effect may be kept up for a length of time. It increases the perspiration, and often to great extent. Whether the nitro-muriatic acid be applied to the inner surface of the stomach, or to the external surface of the body, the effect is the same in kind, though not in degree. As a very general rule for its employment, it may be observed, that, whenever the mercurial preparations are indicated, the nitro-muriatic acid will be found useful, with this difference, that, in cases where mercury is highly injurious from delicacy or peculiarity of constitution, or from other causes, the nitro-muriatic acid may be employed with safety and advantage. On the other hand, I should not at present recommend it in acute diseases, with the exception of some kinds of fever, and of hepatitis of every cha racter. Where the pulse is quick, and where there is an inflammatory tendency, I think it would be injurious.

I was first led to the use of the nitro-muriatic acid from an attention to the diseases of the liver. The derangements of that organ, and of its secretion, open a vast field for inquiry, which has been but imperfectly explored. I shall, as an example of the application of the nitro-muriatic acid, say a few words on this important subject.

Acute and Chronic Hepatitis.

With regard to acute hepatitis, if pure and unmixed, the propriety of employing the nitro-muriatic acid might admit of a doubt; but the same observation may be applied to mercury. I think, how. ever, that I never met with a case of acute hepatitis that did not partake of the chronic affection, either at its commencement or soon afterwards. I know, from experience, that, within the tropics, where I lived so long, a proper use of mercury is never to be neglected in either affection of that organ. I have not trusted to the acid where I thought the risk of abscess considerable; but without delay have employed mercurials, and every other means in my

* Since I wrote the above, some of my friends, as well as myself, have used, for sponging the skin, chlorine dissolved in water, and with the same effects exactly as arise from the union of the acids.

power,

power, to prevent, if possible, a termination so lamentable. I should now not hesitate to add this new power to the other means; and have no doubt, if really insufficient of itself, it would greatly aid us in affording security and relief.

Chronic hepatitis is a far more common disease than the acute; but it may be considered as always partaking of the nature of both. One portion of the same liver is often insensible, enlarged, and inactive, while another part of it is suffering from all the symptoms of acute hepatitis, and going on to the formation of pus. It is this mixed disease that we meet with so generally in India, as well as in this country; and it is this state of the liver which gives rise to so great a variety of anomalous symptoms.

For this chronic affection, it appears to me, that the nitro-muriatic acid applied to the skin is the most effectual and the safest remedy. A few hours, or even a single hour, will sometimes bring relief; but it is necessary to continue the remedy till the system be sufficiently affected by it, and to repeat it occasionally till the patient has recovered his usual degree of strength. This is a rule, in affections of the liver, of the utmost importance. A state of weakness, however produced, is the great remote cause of those chronic affections; so that we may remove the disease, but, till the strength and vigour of the circulation be restored, we have no security against a return of it.

This affection of the liver produces a vast variety of diseases, to which various names have been assigned. To describe them welt would require much time, and occupy many volumes. The process of digestion has an intimate connection with the bile: if this be depraved, the stomach and intestinal canal partake immediately of the disorder. The brain, which seenis to be the source of feeling and motion, is connected, by means of numerous nerves, with those abdominal viscera by which so many of the functions of life are carried on. A diseased state of the bile has a wonderful influence on the whole nervous system: it gives rise to pain and giddiness of the head; a great dislike to motion, and a sense of weakness, rather than actual weakness; cramps come on in the legs while asleep; the soles of the feet are tender and painful, and at times the sick rather drag them than raise them when they walk. A most able and intelligent friend, who was lately relieved very suddenly by the nitro-muriatic acid bath, from a state of long-continued nervous irritation, is of opinion, that all the misery he had suffered for years arose from a depraved state of the biliary secretion. His observations on himself are curious, and very important. He had long taken notice that the bile, though at times ample in quantity, was insoluble in water; and that the fæces had lost entirely the fæcal odour. The solubility in water, with this peculiar odour, gradually returned from the use of the remedy, while at the same time the irritability of the nervous system was suddenly corrected. But I think there is sufficient evidence that this acid, in some cases, acts directly on the nervous system; for in some people I have seen it very suddenly produce a sense of composure, of quiet, and of hap

3

piness,