stage of the disease, though it begun as ordinary sthenic pneumonitis. The positive effect of injurious drugs and the negative influence of neglecting to rebuke disease at an early period, may, in this case as in dysenteria, so deprave the blood and reduce the vital powers, as to get the system into a state similar to that which is produced by miasma or malaria, or whatever creates typhoid fever.

Sometimes pneumonitis has characteristics which have given rise to the term bilious. When the disease is on the right lung especially, that the inflammation should extend to the liver which is separated from that lung only by the diaphragm, and that it should affect, to some extent, the secretion of bile, is perfectly natural. If, however, the phrase bilious pneumonitis may ever be employed with propriety to express any complication of this kind, I think it should be limited to those cases in which, through some epidemic influence, the biliary disturbance is considerable, and the disease has, on the whole, a decided typhoid character. It sometimes happens that, not only the skin and the urine are yellow with bile, and the matter ejected by vomiting is bilious, but the sputa, also, are deeply tinged with bile,-they forming a part of the bronchial secretion. In such a case, if in any, we may apply the phrase bilious pneumonitis; for the biliary disturbance actually affects the pulmonary secretion. This, however, is only a modification of typhoid pneumonitis.

When pneumonitis assumes the typhoid type, some of the general symptoms are decidedly different from those of the usual form of the disease. For instance, instead of a forcible, we have a feeble, and, instead of active excitement in the capillaries, we have diminished' action. We have, also, a rapid prostration of strength; a thickly coated and sometimes a parched tongue; sometimes, too, a delirious or comatose state of the mind; in short, we have, to a greater or less extent, the symptoms of typhus or typhoid fever. In this case, the prognosis is very unfavorable.

The treatment of pneumonitis typhoides, is, in some respects, unlike that of the other asthenic forms of the disease. It must be stimulating and expectorant; but the ordinary bitter tonics will not, to any extent, be borne. On the contrary, the treatment must be diaphoretic and anti-febrile. Wine, ammonia, and like

stimulants may be used, in connection with the expectorant and diaphoretic powders already recommended in the ordinary sthenic pneumonitis. Senega, eupatorium, &c., are also indicated. If delirium or coma occurs, a proper regard must be had to the brain and nervous system. If the bowels become constipated or relaxed, they must receive attention accordingly. The condition of the kidneys, too, must not be overlooked. The opportunities to aid nature, being, at least, but limited, no means within reach should be neglected.

SECTION III.

LOBULAR PNEUMONITIS.

This is sometimes called the pneumonitis of young children, for the simple reason that they are specially subject to it. It is, however, not confined to them, but is sometimes experienced by adults.

PATHOLOGY.-The disease, when it takes place, is not commonly limited to one lung, but extends to both. Instead, too, of its attacking only the lower portion of the lungs, it spreads itself over a considerable extent. But it does not spread uniformly over

the substance of the lung from boundary to boundary. It attacks some lobule or lobules in one part, and then passes over to others a little remote, leaving the intermediate tissue in a healthy condition. As the disease advances, the portions thus inflamed become more and more numerous. Those that were left in health become affected; and, at length, sometimes, the greater part of the parenchyma is found consolidated.

In this form of pneumonitis, the inflammation seems to commence in the smallest bronchial tubes and spread to the vesicles and the several tissues of the affected lobules. Indeed, it is very commonly the sequela of bronchitis in children,-the inflammation of the larger tubes passing to the smaller, and thence to the parenchymatous tissue generally. As the lobules in juxtaposition have no direct bronchial communication with each other, the inflammation has no direct tendency to extend to contiguous lob

ules. By the course of the tubes, remote lobules are just as intimately connected as contiguous ones; but, after certain ones, however scattered, are inflamed, if the disease continues to extend, it must reach those remaining.

In lobular pneumonitis there is, too, another peculiarity. Sometimes the disease scarcely amounts to inflammation. To a great extent, the lungs are only passively congested, and there are but slight inflammatory traces. Hence, in children particularly, the lobules first and most affected are those at the posterior part of the lungs, simply because the blood, while the child is recumbent, gravitates towards that part. The color is a deep red or brown, and sometimes dark. The part affected is generally darker, smoother, and more imperfectly granulated than appears in ordinary hepatization;—just what might be expected from the coagulation of the blood in the congestion and the obstruction to the process of granulation. Such being the peculiarity of the affection, it passes with difficulty to the stage of suppuration. The pleura, too, is less liable to become inflamed by the progress of the disease, than it is in ordinary pneumonitis; but the bronchi, being earlier affected and more exposed to inflammatory action, secrete the usual viscid mucus of the bronchitis of children.

DIAGNOSIS. The constitutional and rational symptoms of this disease are, in general, much like those of the bronchitis of children. They give considerable pyrexia or symptomatic fever, generally, a congested state of the capillaries, especially those of the face or of circumscribed portions of its forming patches on the cheeks; but sometimes paleness and lividity of countenance; an accelerated pulse; a painful cough; and a good deal of dyspnoa, manifested by the distention and contraction of the alæ nasi.

The physical signs of lobular pneumonitis, so far as they can be conveniently obtained, are partially, though not very nearly, like those of bronchitis, in its developed stage. There are the sub-crepitant and the mucous rales, formed, in the largest and the medium-sized bronchi, by the existence there not of pus, but of a mucous secretion, as in bronchitis. The respiration seldom or never becomes so completely of the shrill bronchial character, as it generally is in the hepatized part of a lung in ordinary pneu

monitis. As the disease advances, however, this character is more fully attained, until it, indeed, becomes quite marked. Percussion, at first clear, becomes gradually dull, until it approaches the flatness produced by ordinary hepatization. As it is rare, however, for any considerable portion of the lung, in this disease, to become perfectly solidified, so the dullness does not, at any point, become the most perfect. In estimating the degree of dullness, produced by the disease, in lobular pneumonitis, we labor under one disadvantage. The fact, that both lungs are usually affected simultaneously forbids, in this matter of percussion, the immediate comparison of the diseased with a healthy portion of pulmonary tissue. By having in mind, however, a tolerably correct idea of the resonance which would exist in health, we can, with some degree of accuracy, judge how great is the departure from the normal standard. On the whole, the disease is recognized with an accuracy sufficient for practical purposes. The only essential uncertainty respects the dividing line between the simple bronchitis, with which it usually begins, and that bronchitis attended with inflammation of the pulmonary lobules.

The prognosis in this disease, if it is not complicated with other grave diseases, but exists as a simple primary affection, is favorable. The abdominal viscera are liable to be affected, giving rise to indigestion, vomiting, diarrhoea, or constipation. The brain, too, not unfrequently is congested by an obstruction of the circulation; and the consequence is delirium, stupor, or coma. Such cerebral symptoms indicate far more danger than any abdominal. Besides, they conceal or very much modify the pectoral signs, and, in some cases, almost obliterate them. For illustration, while the patient is under the influence of coma, not sufficient nervous power is conveyed to the bronchial tubes to admit of their sensible irritation by their morbid contents, and, hence, the cough ceases. Of course, in such a condition, the true character of the malady is exposed to be overlooked; and the liability to have the most appropriate treatment neglected, constitutes a part of the patients' danger. But sometimes lobular pneumonitis succeeds to phthisis, dysenteria, or other exhausting disease; and then, of course, the prognosis is more unfavorable.

TREATMENT.—This does not differ materially from that of ordinary pneumonitis,-the doses and the circumstances of their administration being accommodated to the age and condition of the child. The expectorant and anti-febrile treatment, together with a proper regard to all the excretions, is essentially all that is requisite. Revulsives, however, in this disease, should be relied on in the treatment of children, more even than in the treatment of adults. Hence an elm and lobelia poultice, or a paste made mildly stimulating with mustard, or, what I like still better, an onion poultice, may be applied extensively over the chest. Some similar article, too, may be used in the form of drafts upon the feet. A frequent use of the alkaline wash over the greater portion of the body is serviceable; and if the pulmonary inflammation produces much heat externally, a wet cloth applied to the chest anteriorly, laterally, and even posteriorly, will have a salutary effect.

In mild cases, however, a copious secretion from the bronchial tubes, with free expectoration, will cure the disease; and nature will sometimes, unaided, effectually employ this mode of cure. If, therefore, the symptoms do not indicate severity, it may be safe to rely on milder means. In such a case, an occasional dose of the compound sirup of lobelia and sanguinaria, the wine of ipecacuanha, the sirup of onions, or some similar expectorant may

be all that is essential.

SECTION IV.

SECONDARY PNEUMONITIS.

Pneumonitis sometimes occurs as the sequela of some other pulmonary disease, particularly of bronchitis and phthisis. In the former case, both diseases consisting in inflammation, the one is, in a sense, absorbed by the other.

The connection, however, of phthisis with pneumonitis is very different. The two diseases have an intimate pathological relation, and cannot be converted directly the one into the other. But the existing tubercles unquestionably embarrass the lung in regard to resisting the progress of inflammation; or, at any rate,