the disposition, we are told, prevails, to ignore the prevalence of periodicity, although quinine is pretty freely used in the treatment of fever, but it is given as a tonic, and not as an antiperiodic remedy.

Whenever we attempt to treat of fever, about the cause and character of which so little is known, we must, to be practical, confine ourselves mainly to the various phenomena which the disease presents to our observation, from its inception to its close. And nothing can be more important, in this practical point of view, than to determine accurately the relation which the constitutional disturbance bears to the local congestions and inflammations which attend upon it. In the pursuit of this inquiry for ages past, authors have constantly differed in regard to cause and effect; some contending, as we have seen, that fever is an effect and a symptom of some local affection; and others, that it is more commonly a primary and essential disease, and an exciting cause of local derangements. Divested of the influences of all preconceived hypotheses, this is, in every case of fever, a mere question of fact; and we must look to facts rather than to idle and fanciful speculations, if we wish to arrive at correct conclusions. Let us therefore consider what facts teach us; many of you have observed them already, and you may observe them in your intercourse with the sick, daily.

It often happens in this country that a person, com

ing from a healthy region into one where periodic fever is prevailing, begins, in a few days, to feel some degree of indisposition. At first it is slight, temporary, and scarcely noticeable; but it increases from day to day until developed into a distinct chill; and the occurrence of this chill is the first convincing proof he has of the nature of his insidious malady. The chill is followed by the hot and sweating stages of the febrile paroxysm, perhaps only obscurely defined, and the subject is, to all appearance, well again. The paroxysms return, however, at the regular quotidian or tertian periods, and become more distinct and violent at each successive repetition. After a while, signs of some particular local disorder begin to appear, and this local affection, constantly increasing in violence, becomes, in due course of time, the most troublesome feature in the disease, and the principal obstacle in the way of treatment. Sometimes, indeed, if relief be long delayed, this local disease becomes an obstinate chronic affection, which continues to afflict the patient long after the fever has been arrested. Now, to contend, in such a case, that the local disease was the primary, and the fever a secondary affection, would be to acknowledge, for the sake of sustaining a theory, that such local lesion may exist, and to an extent to disorder the whole system by sympathy, without our being able to detect even its

existence; and this no physician would like to acknowledge.

Again, a man in full health arrives at New-Orleans from beyond the seas, while the yellow fever is epide mic in that city; he sleeps there a single night, and then passes on up to Memphis. Perhaps on the third or fourth day of his voyage he complains of nervous depression, headache, and loss of appetite. These symptoms recur and increase from day to day, with alternations of excitement, both bodily and mental, until the eighth or ninth day, when he first experiences a distinct, but moderate chill. A febrile exacerbation succeeds, slight and seemingly unimportant at first, but becoming more and more violent every hour, with constantly increasing pain in the head, back, and limbs, a short morning remission, quickly followed by a still more violent exacerbation, until, perhaps, on the third day from the chill, there is a sudden abatement of all these painful symptoms, and malignant gastritis appears, with all the appalling concomitants of this fatal disease. In two days more the life of the patient is extinguished, with copious ejections of black vomit.

Now, this is a case of yellow fever, contracted, as is not uncommon, by sleeping a night within the sphere of its epidemic influence. The gastritis, which appears as a prominent symptom at so late a period of the disease, is, according to all writers on the sub

ject, the characteristic lesion, and without which yellow fever does not exist. Is it, in such a case as I have supposed, the primary affection and cause of the fever? Nothing could be more improbable; for this formidable disease does not exist for several days without making its presence known. The suffering in the head, back, and limbs, in this case, is the legitimate effect of fever from any cause whatever, and with these symptoms alone, the patient may often be cured by very simple remedial measures. But when, from epidemic influence, or some other cause not understood, the stomach becomes involved, and the physician has to contend with malignant gastritis complicating remittent fever, the disease is beyond the ordinary resources of the profession, and recoveries are only the exceptional cases.

We have seen that some authors have made fever to be dependent upon conjectural changes in the constitution of the blood and other vital fluids, and some upon disordered action of the solids. Others, again, have contended that the brain and nervous systems should be primarily influenced by the exciting cause. To these hypotheses have been superadded others, concerning pathological conditions in some degree incidental to febrile action, having relation to the existence of spasm, constriction, excitability, debility, local irritation or inflammation, follicular and membranous disorder, etc. But all these appear to have

been founded only upon assumed facts, or deduced from deceptive post-mortem appearances. It has not been proved, in a single case of fever, that these changes in the constitution of the blood, the condition of the solids, the action of the brain and nervous system, the spasm and constriction of the capillary ves sels-if any such there be the existence of debility, excitability, local irritation, or follicular and membranous inflammation, one or all, have always existed as a condition precedent in idiopathic fever. No one of these conditions has been proved necessary to the existence of fever, nor is any one of them certain to produce fever, when it occurs from any other cause than fever itself. If, then, fever may exist without any of these conditions, and each and all the conditions exist without fever, we may safely conclude that they are not the proper causes of fever or in any way essential to its existence.

Notwithstanding the general belief, in times past, that a final quietus had been given to the humoral pathology, a strong disposition has lately been shown to revive it, or at least to acknowledge the primary disorder of the blood as the cause of fever. Physicians have, indeed, ventured to proclaim fever a blood disease, professing to have ascertained, that even the graver forms, so fatal to northern men in hot climates, are due to a deficiency of saline materials in the blood. This deficiency is supposed to be caused by