Quartans vary as much; but, indeed, in this country quartans are uncommon, except in the marshy countries on the east of this island. The quartana duplicata of Sauvages consists of two paroxysms every fourth day, and on the other days none. The quartana triplicata consists of three paroxysms every fourth day, with three days of intermission. The quartana duplex has only an intermission of the third day, and the paroxysms of every fourth day are alike. The triple quartan attacks every day; and the paroxysms of every fourth day resemble each other. This disease, like the double tertian, is distinguished by the period of the attack and the shortness of the paroxysms. The author of this article, in thirty-five years practice, has seen but one quartan, which was imported from a distant county.

Quotidians vary but little, except in their causes and their partial attacks. Many of these are symptomatic only; but the partial quotidians attended with violent pains are peculiarly distressing, and with great difficulty removed. The quintana and septimana are described by authors very vaguely, and seem, in general, to be symptomatic.

Intermittents are not always dangerous, and the vernal agues generally disappear on the approach of summer. The autumnal ones are more frequently attended with infarctions of the liver, and the more obstinate kinds of these, the quartans, leave often this organ in a scirrhous state. Dropsies and hectics are the consequence. It has been, on the other hand, contended; that vernal tertians are salutary, and clear the constitution of other diseases, as indigestion, flatulency, and acidity of the stomach; habitual rheumatisms and other inflammations; cutaneous and nervous complaints. For this opinion we offer the very respectable authority of Dr. G. Fordyce, for having seen but few cases of intermittents, we will not add, as an ojection, that such salutary effects have not occurred to us. We have found every intermittent, which we have seen, to be a disease which we have been anxious to cure as speedily as was consistent with the safety of the patient.

The cause of intermittents is exclusively the miasma from marshes, and the remote causes those of fever in general. We have already observed, that no satisfactory reason has been assigned for the recurrence of the paroxysm. Dr. Cullen attributes the duration of fevers to the violence of the spasm or the weakness of the reaction; and though in each paroxysm of intermittent the spasm may be conquered, yet its cause, the atony, remains to be combated by a new series of symptoms. It is evident that in intermittents the cause remains, for they leave a languor, in part the effect of the exertions; but, in part also, of the remaining debility. While we have modified, in some measure, the doctrine of Dr. Cullen, yet this explanation, with a change of the language, may appear probable; and it is supported by a fact already stated, that the concluding paroxysm is the most violent. We know not, however, the duration of an intermittent in consequence of the debility remaining unsubdued; for we shall find, that it is often continued from habit, and that raising any violent emotion, fixing the attention, or exciting a different train of motions, in any way, will prevent its recurrence; and, when once prevented, the fit seldom returns. It may be then questioned, whether, even in the early stages, it may not be the creature of habit. When an intermittent first attacks, its paroxysms are seldom regular. When they become so, they soon establish a habit which we know is with difficulty removed; but this habit seldom takes place but in weak, mobile constitutions.

In the cure of intermittents, our first object is to prevent the recurrence of the fit; our second to conduct the paroxysm, so as to obtain a complete solution of the disease; the third to increase the general tone of the system, in the intervals, that the disease shall not again return.

Our first object, for it is not strictly an indication, is limited to those remedies whose immediate action may prevent the attack. These are means of increasing the tone of the system, or supporting the action of the extreme vessels, so as to prevent their quiescence, perhaps their spasm. The tone of the system is increased by stimulants and tonics. With this view aromatics.

the strongest acids, and ardent spirits, in almost every imaginable variety of form, are administered when the fit is expected. Very large doses of bark are also given, so as to accumulate from one ounce to two in the stomach, at the time of the usual return. The former of these plans is highly injurious when a phlogistic diathesis prevails in the system; for it converts the intermittent often into a continued fever, with topical inflammation. The latter is equally injurious, when the stomach and bowels have not been previously cleared; and occasions those infarctions styled ague cakes, which have been so often attributed to the bark.

In different circumstances each has succeeded.

The action of the extreme vessels is supported by emetics and sudorifics. An emetic is given previous to the return, while the perspiration is supported by warm negus, the volatile alkali, or the sudorific powder of Dover. Opium, with warm leas, will equally succeed; but, in general, for the reasons formerly assigned, great external heat should be avoided. Opium is not the only medicine which acts peculiarly on the vessels of the skin, though it is the most powerful. Guaiacum has a similar effect; and the ammoniated tincture, when joined with opium, is often a valuable remedy used with these views. Musk, empyreumatic oil, and ether, are said to have had a similar effect, without producing sweating; but in such cases, they probably, if successful, which has been doubted, act as simple stimuli. To the same source may be attributed the effects of bracelets of mustard seed and garlic to the wrists and ancles; bruised spiders and tobacco, applied to the wrists; yarrow, & c. to the feet. These excite so great a degree of inflammation as to increase the heat as well as the circulation, and have often undoubtedly succeeded. We must add, that whenever we attempt to prevent the paroxysm of an intermittent by sweating, this mode of relief must be continued till the period of the paroxysm is at an end, or at least till the time when the sweating stage would have otherwise commenced. Those means which excite terror, surprise, and horror, or, as we have said, raise a train of new emotions, will prevent the return of paroxysms. A man has been pushed into the water; fire has been cried; the most distressing tidings invented and communicated. A patient, labouring under an ague, has been ordered to swallow half a pint of his own urine; to hold a toad in his hand till it dies; to eat common spiders in a raisin, or cobwebs in crumb of bread. All these remedies fill the mind with such dread as to counteract the impression of the cause; but in general they are dangerous, and when we wish to prevent the fit, we depend rather on the tonics, the stimulants, and the sudorifics. These are often highly necessary; for when the fever attacks with apoplexy, epilepsy, or other symptoms which threaten the life; or when the patient is so far debilitated that another fit would be probably fatal; we must take the most decisive steps to prevent it. We remember to have seen three cases of this kind, in which by the sudorific plan, detailed above, we succeeded.