1st.-VENESECTION.

Blood-letting is as ancient as the wars of 'Troy, and the practice of Podalirius. If Hippocrates neglected it, Areteus, Celsus, and Galen, made ample use of this important measure. It is true, that even in our own times, the dogmas of the schools had nearly proscribed for awhile, what nature and observation had pointed out from the earliest dawn of medicine to the present time, in every climate from the banks of the Scamander to the vales of Otaheite.

The bounding pulse, the fever-flushed cheek, the throbbing temples, and aching head, must indeed have vindicated the propriety of blood letting in every æra, and in every mind not warped by the bias of some fashionable doctrine.

In these scrutenizing days of investigation and experiment, the lancet has dispelled the mists of prejudice, the phantoms of debility and putrescency, with the delusions of the Brunonian school; and bleeding is justly regarded as the paramount remedy, not only in symptomatic, but in all the more violent and fatal idiopathic fevers.

The consonance of this measure with the principles I have laid down, is so evident as scarcely to need comment. When the balance of the circulation is broken, and determinations take place to one or more organs, the most effectual means of restoring the balance, and of relieving these organs or parts from their overplus of blood, will be found either in local or general abstraction of the vital fluid. It is not from there being less than usual of blood, in some parts, but from there being too much in others, that the danger consists, and that we are called upon to reduce the whole mass below par. Nature herself invariably printout d is indication, and in perhaps a majority of instances. inlbis it in her own way. Thus we find that every paroxysm of fever is terminated by some evacuation from the system, whether by perspiration, urine, increased secretions, or some local hæmorrhage. In what is called continued fever, the nocturnal exacerbations are terminated in the morning by some slight modifications of the foregoing evacuations; and in all fevers and all stages of fever, nature effects depletion by preventing repletion; and hence that invariable attendant on fever anorexia is one of the wisest and most salutary measures which nature can put in force to finally overcome the disease; though she is too frequently baffled in her attempts by The officious interference of the cook, the nurse, or perhaps the medical prescriber.

shall now make a few remarks on the most judicious manner of employing this remedy in fever; for on this, in a great measure, depends its success; and to the contrary, I believe, may be attributed not only its failure, but its disgrace.

In the first place, the time for blood-letting in fever should be an object of great attention. It should not only be early in respect to the accession of the fever, but the acme of the paroxysm or the height of the exacerbation should be selected as the proper periods for making the abstraction. At these times the evacuation will produce an alleviation of symptoms, and often a solution of the paroxysm

or exacerbation; whereas if taken during the remission of the fever, when the system is, as it were, in a state of collapse, deliquium animi is often the consequence, followed by a train of nervous symptoms and debility that are charged on the measure, when they ought to be placed to the account of the ill-judged period of its application.

The manner in which blood is drawn ought not to be neglected. When any strong determination to the head, or other organs exists, the vascular system so accomodates itself to the loss of blood from a thready stream that little or no relief is obtained for the suffering viscus, while the general strength is unnecessarily reduced by the quantum lost.

Although we are to be much less guided by the appearance of the blood drawn, than by the order and violence of the symptoms; yet as a certain coat or crust of fibrine very generally, though not invariably, covers the coagulum when there is any local inflammation going on, we should attend to those circumstances in the abstraction that are favourable to the development of this criterion. Thus the stream of blood - should be free and of a good size; and it should be received into the centre, not impinged against the side of, a narrow and rather deep basin, with a polished internal surface. If the reverse of these directions be observed, as is too often the case, the blood will not exhibit any inflammatory buff, though inflammation be actually present at the line.*

As in fevers as well as some inflammations, it is not so much the general plethora of the vascular system, as the broken balance of the circulation that is to be corrected, so local abstractions of blood from the vicinity of those parts where the congestion or determination exists, are often of more importance than general blood letting.

It is to be regretted that, whether from the prejudices of the patient or the inattention of the practitioner, the seat of the determinations in the fever is rarely ascertained and relieved by topical bleedings. The violent headache, indeed, and arterial pulsation at the temples, frequently draw the practitioner's attention to that part, and leeches are accordingly applied; but the epigastric region, where there is always more or less fulness, and to which the vital fluid seems in most fevers to gravitate, is too much neglected. Leeches or scarifications should long precede the necessity for blisters in these parts.

The ancient physicians had a very limited range, and a very rough list of purgative medicines. They made, however, a considerable use of them. Of late they were almost neglected by Cullen, and proscribed by Brown, in the fevers of this country, unaccompanied with topical inflammation. Dr. Hamilton and the greater number of modern practitioners employ purgatives freely, without fear of that far-famed, and much dreaded debility. The principle on which

"Vide the inestimable work of Dr. Armstrong on Typhus. Also Dr. Dick: son's writings on Tropical Fever.

these act, in fever, are by no means generally understood; and the practice itself is inefficient from this cause. Even Dr. Hamilton seems to attribute most of the good effects of purgatives in fever to the removal of irritating fecal remains. But if this were the case, the glysters of Cullen would have answered the same end, which, however, they did not. The removal of fecal accumulations, from the small intestines particularly, gives a more free descent to the blood through the abdominal aorta and its branches, and thus mechanically assists in the restoration of balance; the increased secretion from the mucuous membrane of the alimentary canal, must also powerfully deplete the cæliac vascular system; but a very salutary modus operandi of purgatives in fever, has, I believe, escaped the notice of physicians, althongh I conceive it to be an important one; I mean the change from torpor of the intestines to a brisk peristaltic motion, whereby the blood which has been shown to accumulate, and as it were stagnate, in the portal circle, is propelled forward, and the biliary secretion increased. Another salutary effect is produced by the sympathetic influence which the internal surface of the alimentary canal exerts on the cutaneous surface of the body; for although drastic purging will check profuse perspiration, yet where torpor pervades both the internal and external surfaces of the body, a restoration of the functions of the former contributes to the same event in the latter; a fact, of which any one may convince himself at the bed-side of sickness by an attention to the circumstances under con. sideration.

When therefore the peristaltic motion, the gastric, and intestinal secretions are roused by purgatives, the bead which, from the peculiarity of its circulation, must suffer sanguineous congestion, is almost immediately relieved by the change of balance, thereby induced. From these considerations it will not appear a matter of indifference, what purgative medicine we use. Experience has taught us that some, (for instance castor oil,) do little more than clear the intestinal canal of what already exists there; that others, (for instance the neutral salts, jalap, &c.) produce copious watery secretions into the alimentary tube, during their operation;-and that others still, (for instance the submuriate of quicksilver,) besides acting as a common purgative, increase particular secretions, as of the bile, and carry them off, whether in a healthy or morbid state.

From the importance of the hepatic function in the animal economy, and bad effects which result from any derangement or obstruction of it in febrile commotion, it is evident, and experience proves it, that into the combination of purgative medicines in fever, those of a cholagogue power should almost always enter. Hence it has been found both in this and other countries, that powdered jalap and submuriate of quicksilver formed a composition most admirably adapted to the purposes above mentioned, as may be seen by the writings of Rush, Jackson, Hamilton, Armstrong, Dickson, &c.

Hence also, we see how purging, by rousing the torpid circulation and excitability of the abdominal viscera, determining the blood through the various branches of the aorta which were before choak

ed up, and thereby removing the congestion in the head, restores strength, by relieving the sensorium, instead of adding to the preexistent debility, as was dreaded by the Brunonians and Cullenians, and which dread still fetters the hands of numerous practitioners even in this country. The operation of purgatives then, is perfectly consonant with, and elucidates the fundamental principle, to be kept in view in fever-" a restoration of equilibrium in the balance of the circulation and excitability."*

The operation of these apparently different measures, in mitigating or even arresting fever, is in perfect consonance with the principle laid down.

Leaving out the effect of sensation on the nervous system, during the affusion of cold water on the febrile surface of a patient, it is evident that the violence of reaction, (at which time alone it ought to be applied,) is mitigated by the cold, while the febrile irritation of a strictured surface is taken off.

That these objects tend to a restoration of balance in the circulation and excitability, need not be insisted on ; the other effect of cold affusion, namely, a subsequent perspiration, will also be found to have a similar tendency.

The effects of tepid affusion during reaction, or the hot stage of fever, is precisely analogous to that of the cold, only less forcible in degree; for it must be remembered that the tepid bath is, or ought to be of a much lower temperature than the surface of the body, when applied in the hot stages of fever, and consequently acts in reality as a cold bath, only in a much more gentle manner.

When it is applied in the cold stage of fever, its operation in drawing the blood to the periphery, and thus restoring the balance of the circulation, is direct and obvious; while in restoring sensibility to the torpid skin, the balance of excitability, is, of course, equipoised. The action of cool air in fevers is easily explicable on the same principles.

4th.-MERCURY.

Various have been the disputes respecting the operation of mercury on the human system. A stimulant property has been very generally attributed to this mineral, apparently from its quickening the vascular action, and " exciting an artificial fever."† Hence," says the Enquirer [loco citato] "its efficacy in remittent and continued fevers is very equivocal. At the commencement of those diseases I believe that it does mischief, if exhibited in any form to exert its power on the salivary glands alone." It would be difficult to select

* Vide Dr. Dickson's admirable papers in various numbers of the Edinburgh Medical and Surgical Journal.

t Ed. Journal, vol. vi. p. 181.

a passage in any medical work which contains so much error and so much want of knowledge, in so small a space, as the above paragraph. In the first place, those who condemn the use of mercury most, condemn it on this principle, that in some very concentrated forms of inflammatory fever, as the endemic of the West Indies, it cannot be brought to exert its influence on the system in time, and therefore there is danger in trusting to its operation. Mr. Sheppard, of Witney, one of the ablest of the anti-mercurial party, expresses himself thus - The co-existence of febrile and mercurial action is generally admitted to be incompatible; if, therefore, the action could be superinduced in violent fever, we should be possessed of an invaluable remedy."-Ed. Journal, October, 1817.

In the second place, who ever saw mercury affect the salivary glands alone? Narrow indeed, is that view of the mercurial action which stops short at its quickening the pulse, "and exciting an artificial fever." The fact is, that ptyalism is merely a symptom that the salivary glands are affected, in common with every other gland, and every secreting and excreting vessel in the system. Thus floodgates are opened in all directions, and every part of the human fabric experiences a rapid diminution-in short, mercury is never more an evacuant than when it produces ptyalism. This general depletion is still further increased by the ptyalism preventing any supply of nutriment which the patient or friends might wish to introduce.

I am ready to grant, indeed, that in certain high grades of the western endemic, or yellow fever, we cannot bring on this much desired effect of mercury; and why? Let Mr. Sheppard himself answer the question. "From the experience of many years within the tropics," says this judicious observer, "I am disposed to coincide with those who believe that the disease, in the highest degree of concentration, is irremediable by any known means in medicine; for I have remarked, in this extreme case, that whatever plan of cure may be adopted, the rate of mortality remained unaffected by variety of treatment." Loco citato. Now if mercury fails in these cases, so does depletion; but I most solemnly protest against the inference that, because pyrexia ceases when ptyalism appears, the latter is merely an effect or consequence of the former.

In the inflammatory forms of West India fevers where hepatic congestions are comparatively rare, I conceive that depletion alone is the best mode of treatment; but to draw a sweeping conclusion from this circumstance that mercury is totally useless, if not injurious, in all febrile states of the system, and in all climates, is most erroneous in principle, and injurious in practice. The ensuing pages of this essay will afford ample illustrations of the febrifuge powers of mercury; while its modus agendi, as an equalizer of the circulation and excitability, will be found to be in exact consonance with the principles here laid down.

5th.-EMETICS.

The gastric irritability which accompanies most fevers might have led to the suspicion that nature aimed at relief by unloading the