Of exhaustion from excessive secretion we have examples in the effects of colliquative sweats, diuresis, and diarrhoea, and of copious mucous discharges from the bronchial tubes and urinary passages. In these cases, quinia sometimes acts happily, not only by sustaining the system under the exhaustion, but by correcting the excessive discharge, which itself not unfrequently depends on a pre-existing debility and relaxation. But astringents are generally still more useful here than quinia, which may often be advantageously associated with them; and it is probable that the infusion, decoction, tincture, or extract of bark may be more useful than the alkaloids, in consequence of the tannic acid they may contain.

The same remark is applicable to passive hemorrhages, which at once depend upon and increase debility, and in which the conjunction of astringents with the preparations of bark is often indicated.

Another condition of debility, in which this medicine is highly serviceable, is that produced and kept up by some directly depressing agency, independently of any exhausting discharge. Such are all those conditions of the system in which extensive gangrene has taken place, or even a small degree of it, if in one of the internal and vital organs. How it is that the connection of a mortified part with living tissue should produce general prostration is not always very evident; bu1 such is certainly the case, even where there has been do preceding debility. When the debility gradually ensues, and is attended with typhoid symptoms, there has probably been absorption of the deleterious matters resulting from putrefaction, and a consequent contamination of the blood. But frequently the result is too sudden to admit of this explanation. A part dies; and almost instantaneously the pulse becomes feeble, the skin cold, the countenance pale, shrunken, and ghastly; and, though reaction to a certain extent may take place, yet the energies of the system are still depressed, and continue so more or less until the offending cause is removed. Possibly a depressing effect from the dead matter upon the adjoining nerves may be reflected to the system, through the nervous centres, in the same manner as local irritation. But, however produced, the debility exists, and often requires the interference of tonics and other stimulants to support life, and give the parts power to throw off the offending cause. Certainly, among the tonics there is none so efficient for this purpose as cinchona. So beneficial is it, that an idea formerly prevailed that it possessed a positive and peculiar property of checking or obviating mortification and putrescency. At present, however, this idea is not admitted. All that the bark can do is to sustain the failing energies; and this it is perhaps better able to do than others, because of its stimulating influence on those very nervous centres through which the depressing impression is propagated.

In the gangrenous cases in which a pre-existing condition of system, or depraved state of the blood, has caused the mortification, there is a double indication for the tonic. Hence, the preparations of bark have always been among the most approved remedies in anthrax, gangraena oris, malignant sore-throat with or without scarlet fever, and erysipelas with sloughing of the subcutaneous tissue.

Another large list of diseases, in which debility, depending on a direct sedative influence, indicates the use of bark until the depressing cause shall cease to act, are the typhoid affections. In these, either the morbific cause itself, or the depraved state of the blood resulting from it, acts with a special influence on the brain, producing dulness, stupor, low delirium, and other evidences of cerebral debility. Cinchona, therefore, is specially called for, both for its excitant action on the nervous centres, and the rapidity with which it acts. Typhus fever, the advanced stages of typhoid or enteric fever, petechial or spotted fever, scarlatina particularly of the anginose and malignant varieties, malignant smallpox and erysipelas, and even the phlegmasiae when they assume the typhoid condition, as typhoid pneumonia and dysentery, are often usefully treated with this pervading and powerful tonic. Though of itself insufficient to support life in many of these cases, and therefore requiring the aid of more potent stimulants, as carbonate of ammonia, opium, and the alcoholic liquids, it gives a durability of impression, and power of resistance, not equally obtainable from these agents, and, therefore, cannot be fully replaced by any one or all of them.

In protracted diseases, particularly those of a febrile character, though perhaps sthenic in the beginning, the vital forces are gradually impaired by their over-exercise, and a state of debility ensues requiring tonic treatment. Here too the preparations of bark are the most efficient. It is highly important to know when exactly the period for this treatment has arrived; for, if prematurely employed, it may injuriously aggravate the excitement. I have noticed that the occurrence of night-sweats, under these circumstances, offers one of the best criteria of the new condition. When a patient with a febrile disease, not having been especially affected with diaphoresis, begins to sweat profusely whenever he sleeps, and only then, I consider the symptom as an almost sure sign of debility; and quinia, though previously contraindicated, may now be used with safety and advantage. This condition is quite different from the typhoid. In both there is debility; but in the latter, it is connected essentially with depravation of the blood; in the former, it is merely the result of an over-exercise and consequent exhaustion of the vital forces, and the blood is no otherwise diseased than as it may be deficient in quantity, either considered generally, or in relation to the red corpuscles. My attention has been particularly directed to the condition as it occurs in acute rheumatism, in which it is not very uncommon, though the disease may still be associated with considerable pain and swelling in the joints. Whenever night-sweats take place in that disease, I invariably employ quinia, and almost uniformly with favourable effects, not only checking the excessive sweating, but very much ameliorating if not promptly curing the rheumatism itself. I have been long in the habit of employing and recommending this practice; for many years, indeed, before the recent revival of an old method of treating acute rheumatism by Peruvian bark.

Various derangements of health which have been classed together under the designation of cachectic, the only common characters of which are chronic debility, and a not well understood depravity of system, in which the blood is probably always involved, such as syphilis in its advanced stages, scrofula, and various obstinate cutaneous eruptions, including ecthyma, rupia, and impetigo, are not unfrequently benefited by quinia, in conjunction with certain alterative remedies, as iodine, mercury, and arsenic.

Under this head may perhaps also be ranked the use of quinia in enlarged spleen, especially when following miasmatic fevers, or occurring in malarious regions. Some ascribe the efficacy of the medicine, in these cases, to a property which they suppose it to possess of directly contracting the spleen. But quite as probably it is ascribable to an alteration, under the tonic influence of the remedy, of that condition of system, and especially perhaps of the blood, which originated and sustains the affection. In many instances of enlarged spleen of a different origin, even when there is no reason to suspect cancer, tubercle, or other incurable heterologous formation, quinia proves, as I have often witnessed, wholly inoperative.