This is a faithful picture of the general progress of continued fever, either fatal from its violence, from neglect, or from improper treatment. In more favourable circumstances, or with proper management, the head is less loaded; the tension of the epigastrium is inconsiderable; the tongue continues clean at the edges; some refreshing sleep is obtained every day; and, about the fourteenth, after an unusually restless night, sleep more sound and natural occurs; the pulse becomes softer and slower; the edges of the tongue appear of a more healthy redness; the palms of the hands more moist; the recol -lection clearer. Sometimes these changes are very gradual, and the experienced practitioner perceives them two or three days before they are conspicuous to the attendants. It is not uncommon to find the first appearances of returning health in a whimsical capricious appetite. The patient wishes for something savoury. If brought, it is rejected with disgust. The next object may be more singular, and this may be tasted; a small portion of the next is perhaps swallowed. In other instances, some particular food, very frequently that least pleasing when in health, is eagerly longed for, and as voraciously devoured, without injury. In general, to long for a particular food is a favourable symptom, and a certain proof of returning health.

Intermittents and remittents arise from the same causes, are relieved by the same remedies, and pass into each other. In the former the intermissions are distinct, and no inconsiderable period intervenes in which the patient is free from fever; but on some occasions, from different causes, this period is considerably restricted. Double intermittents, in the circumstances just assigned, often assume the form of remittents; but the error which this confusion would occasion will produce no practical mischief.

It is a general fact, that the longer the paroxysms are protracted, they are sooner repeated; as well as that the access and the fever are violent, in proportion to the shortness of their duration. From this universal law, it is easy to see how intermittents, particularly quotidians, become remittents, and, in their progress, continued fevers. Dr. Cullen explains the variety by the proportional strength of the opponents, spasm and reaction, in different circumstances. It seems to us to depend rather on the weakness of the cause. The fever comes on with the usual diurnal period of febrile exacerbation, remits with its decline, and disappears on its solution. There is, however, a regularity which is not easily explicable. The quotidian attacks with the morning exacerbation, the tertian with the noon, and the quartan with the evening. Are these diseases of different violence in the same order ? There is no other evidence of such an opinion than this, that the quotidian is in general the milder, and the quartan the more obstinate disease; but the appearance of each, in distinct epidemics, is so striking, that there is little de-pendance on such reasoning, and we must leave it with the numerous arcana of the medical science.

Remittents, we have said, are diseases in every respect similar to intermittents, except that fever is never wholly absent; yet there is one remittent which nosolo-gists have reluctantly admitted, and one which, in a natural system, imperiously demands admission: the first is the irregular intermittent or remittent, the erratica, and the second the hectic. So far as we have been able to investigate the former, it is only an irregular hectic, either from visceral obstructions, or from absorbed matter; and the latter is well known to proceed from the absorption of pus.

The continued fevers are probably quotidians only, with protracted paroxysms. In these what is styled reaction is not considerable, and this certainly proves an increased action of a debilitating power; in other words, the introduction of a more deleterious poison. The worst fevers are introduced by the longest cold, and the mildest by the most violent rigors: a circumstance which leads Dr. Cullen to conclude, with great apparent reason, that the rigor is an effect, probably a measure, of the reaction. Perhaps the explanation is nearer the surface: the reaction is in proportion to the irritability; and a powerful debilitating cause will not only weaken the sensorial power, but impair the irritability also. We have decisive evidence of the truth of this explanation, since those who die rapidly from fevers have the irritability of the muscles destroyed as completely as those who are struck by lightning. On the opposite side, it does not appear that the diathesis phlogistica greatly increases the spasm, since the true inflammatory fevers are the shortest. Irritability, we know, is not in proportion to the inflammatory diathesis; and we should not, from our views, suppose such,fevers peculiarly obstinate.

We are unwilling to admit any other variations of simple fever, since those introduced by medical authors seem to be only accidental varieties. Indeed we consider fever as a more simple disease than it is usually represented;and shall endeavour to show, that what are termed genera are only, in a strict systematic view, species, and the reputed species, varieties. But these considerations must not now interrupt us. The principal distinctions, in the bestworks, have been into bilious and putrid fevers; the former comprehending the yellow fevers in all the variety of denomination; the latter the malignant, the petechial, etc. etc. The bilious fevers are, however, those of the tertian type, distinguished by evacuations of bile, from the causes formerly explained; and the autumnal remittents of warm climates. The putrid fevers are the worst kinds of the jail and hospital fevers, where the deficiency of the vis vita; no longer checks the tendency of animal substances to putrefaction; and where, in some instances, even a septic ferment may be suspected.

The prognosis of fevers has occupied many volumes. We can give only the outline. Consistently with the views offered, our prognostics must be taken from the signs and degree of debility, or the diminution of irritability. When Dr. Cullen endeavours to anticipate the event by the degree of reaction, he betrays the weakness of his system, as this state affords few prognostics, and those rather to be attributed to debility. When congestions in the head or in the lungs, for instance, occasion effusion or rupture, these only occur in the last stage of a protracted disease, though attributed by him to the violence of reaction.