There are various peculiar and distinct contagions, which excite fevers of a particular form, attended with cutaneous affections. The jail and hospital fever maybe considered as the consequence of a peculiar contagion; but no cutaneous inflammation is the consequence. The plague connects this with the other exanthemata; but in each the prior appearance of fever, often with peculiar marks of debility, shows that the virus is of a sedative nature. The profluvia of Dr. Cullen also arise from contagious effluvia peculiarly their own.

The effluvia from marshes is now fully ascertained to be a remote cause of epidemics, and of some of the most destructive debilitating kinds. Their sedative tendency-is, therefore, sufficiently obvious; and, as they probably consist of hydrogenous gas, which destroys the irritability of the fibres, its real nature may be easily understood. Marshes covered with water are not injurious; but when the earth begins to appear above the water the epidemics commence.

Bile has been enumerated among the remote causes; but its appearance may be easily accounted for from the explanations already given. When we know it to be diseased, either in quantity or quality, symptoms very different from fever arise.

Putrid vegetable substances have been supposed to exhale effluvia injurious to life, and to be particularly active in producing the worst fevers. This we believe to be sometimes the case; but they more frequently give some peculiarity to the nature of the fever, rendering it more asthenic or putrefactive.

Cold is undoubtedly also a remote cause; but in producing fever it must be actively applied while the body is heated, and the effects can only be considered at length when we treat of inflammation. It is, however, especially when united with moisture, an exciting cause. See Causa, Cold, and Contagion.

Fevers, from a variety of circumstances often not easily explained, assume many different forms. Every fever seems to consist of distinct paroxysms, almost universally concluded within twenty-four hours; and the existence of a continent fever, one which proceeds without any changes, is not at present admitted. To the termination of each paroxysm within twenty-four hours there have been some objections; but the fallacy arises from the existence of double tertians, or the combination of two kinds of intermittents. In these cases the cold fit of the second disease sometimes attacks in the middle of the hot fit of the former, and thus in appearance protracts the paroxysm. Many such instances are recorded by Torti and Senac.

Fevers, then, may be divided into those which have distinct paroxysms, and those in which the accessions and terminations are less distinct. The first include the intermittents and remittents; the second the Continued Fevers.

The symptoms of intermittents are the regular paroxysms, which we have described. When these degenerate into remittents, the cold fit becomes shorter, and is less distinctly marked; the heat is less considerable, and longer protracted; the sweat comes on; but before the complete termination another attack supervenes. In the more continued forms we lose the attack, and in some degree the solution, by sweat. We find only occasional exacerbations of heat, and remissions in which the pulse is more soft and full; the hands cooler and more moist.

In every attack of a continued fever we find, in the commencement, apparent remissions, particularly in the morning. The day passes with tolerable ease; the patient thinks his disease at an end, and the physician flatters himself that he has been too soon alarmed. The succeeding evening, however, ends the delusion, and each following morning the remission is less distinct; though on every morning there is usually a visible amendment.

In the early state of a continued fever there are often wandering pains, which have been considered as rheumatic; and we suspect have occasioned the nosologists to introduce the genus synochus. These pains are apparently often the tensive ones, which we have attributed to irregular action; but they are undoubtedly sometimes rheumatic, and have occasionally, as in one of the epidemic nervous fevers described by Sydenham, attacked the chest, with pleuritic or peripneumonic symptoms. Much inconvenience has arisen from this symptom, since it has led to bleeding in fevers of the worst tendency. We recollect, indeed, but one epidemic in which similar pains were wholly absent, and this was a malignant remittent at Breslaw, described by De Haen, on the attack of which, even previous rheumatic pains disappeared.

When these symptoms no longer occur, continued fevers proceed many days, with little change. Symptoms of debility, to be described by the prognosis, increase; the head becomes more loaded; the patient more insensible, or more delirious; the character of the features is lost, or they are enlarged so as to disguise every former appearance. The pulse becomes more quick; the abdomen more distended; stools at times less frequent, but occasionally numerous, watery, and involuntary; the tendons of the wrist more tense, and sometimes starting with a convulsive motion. The tongue, at first brown only in the middle, is dry, furred, and of a dark red or a livid colour. Its action is lost, and the patient can either not put it out, or it is pushed forward with an unequal, tremulous exertion. The edges, which for some time continue moist, are at last equally dry with the rest; and, for examination, it must be drawn by the fingers beyond the teeth, and replaced. The inability to swallow keeps pace with the changes in the tongue, and at last the power of deglutition is wholly lost. The insensibility increases; the starting of the tendons is followed by convulsive catchings; the patient attempts to pick off some objects from the bedclothes, then sinks into insensibility, from which he is only roused by the last convulsive struggles.