be conducted on precisely similar principles as in that of the adult, and will consist in bleeding, cupping, or leeching, according to the age and strength of the child; the free administration of calomel in combination with either antimony or ipecacuanha; gentle laxatives; diaphoretics; digitalis; mild anodynes; counter-irritants, and the warm bath.

Chronic Pneumonia.

A chronic form of pneumonia is by no means unfrequent in phthisis pulmonalis, around the softened tubercular deposits; it occasionally results from pulmonary apoplexy; but may also be a mere sequel of acute pneumonia imperfectly cured. In the latter case, it most frequently occurs in persons of impaired constitution or of intemperate habits. Whatever may be its origin, this form of pneumonic inflammation appears to produce in the pulmonary tissue, effects analogous to those observed to result from chronic inflammation in other parts of the body. The effused albuminous matter seems to become more or less perfectly organized, so that on examination after death we find the diseased lung remarkably dense, and in some instances almost of cartilaginous hardness; the condensed lung is altogether impervious to air; it is of a very dark colour, nearly approaching to black or occasionally greyish, somewhat like ordinary tubercular infiltration; whilst the surrounding cells are in general more or less charged with a serous-looking fluid.

It is the chronic pneumonia succeeding to a previous acute attack, which alone merits a separate notice; and even this form of the complaint is so extremely rare as to be of little importance beyond the possibility of its being mistaken for phthisis pulmonalis. The history of the

case, however, the character of the expectoration, the absence of any evidence of actual vomica, and the presence from time to time of the crepitating rattle, will probably serve to distinguish the disease in the very few instances in which such a doubt can arise. As it is mostly met with in bad constitutions, the treatment must be regulated accordingly, and may consist of mild mercurial alteratives, with anodynes and diaphoretics, gentle laxatives, digitalis, local counter-irritants, a bland but nutritious diet, and, if practicable, a removal of the patient to a more temperate climate.

GANGRENE OF THE LUNG.

Gangrene of the lung is a rare disease, and is distinguished in a peculiar manner by the putrid odour of the patient's breath, and of the matter expectorated, which so commonly attends it. It is either irregularly diffused over a considerable and variable extent of the pulmonary tissue, or it is circumscribed and limited to a small portion only, constituting a gangrenous eschar. It seldom or never results in either of its forms from an ordinary attack of acute pneumonia, although it is not improbable that some degree of inflammation precedes or accompanies it in every instance. It is most frequently met with in bad constitutions, and especially in those who are habitually intemperate, and who in consequence are exceedingly prone to have gangrene induced by comparatively slight

causes.

When of the irregularly diffused kind, the gangrenous lung is found more humid than natural, softened, easily lacerable, occasionally almost liquefied, and of a dirty white, greenish, or dark olive colour; or from a mixture

of these colours with portions of dark red, a peculiar mottled appearance is produced. On cutting into it, a quantity of thin, sanious-looking, and greenish muddy fluid, of a most insufferably putrid odour, oozes out. This diffuse gangrene may involve a single lobe, or it may extend to the greater part of a whole lung; it sometimes passes insensibly into the sounder tissue, and is generally observed to be surrounded by lung in the first stage, or more rarely in the second stage of inflammation.

When of the circumscribed form, the gangrenous portion of lung is most frequently found of a dark green colour, extremely offensive to the smell, more humid but at the same time more firm than natural, and surrounded by lung in the first stage of inflammation. In other instances the gangrenous portion separates from the sounder tissues, and either remains like a moveable nucleus in the cavity thus formed; or softens down into a fluid, grey, or greenish mass, having a most offensive putrid odour, and giving rise to a vomica, which presently communicates with the bronchial tubes. A vomica thus formed, is sometimes found lined by a false membrane; in other cases, the inflamed and hardened pulmonary tissue itself forms the parietes of the vomica, and seems to pour out an offensive secretion. If the disease be not quickly fatal, such a vomica may induce hectic, rapid emaciation, and death, as if from phthisis; it has been known to open into the cavity of the pleura, occasioning death by pneumothorax; and in some rare cases the vomica has appeared to contract, cicatrize, and the patient recover.

Such are the appearances usually observed on dissection of those who have died with symptoms of gangrene of the lung; these appearances, however, in all probability differ according to the particular state of the lung at the

period of the attack; for experience and dissections incline us to the belief, that in some cases at least of pulmonic gangrene, there had existed previous disease of the organ, and upon which some slight accidental inflammation, or a highly vitiated condition of the constitution, had induced a state of gangrene. We believe it to be in this way that tubercular or pneumonic deposits, and the remains of pulmonary apoplexy, occasionally lead to gan

grene.

When unattended by fœtid breath and offensive expectoration, as occasionally happens, it is not likely to be recognised during the lifetime of the patient, although some suspicion of its existence may probably now and then be excited by the general prostration being disproportionate to the degree or extent of disease discoverable in the lungs by auscultation and percussion. When, however, the breath and expectoration are fœtid, when the latter is diffluent and purulent, or thin, sanious, and of a dirty white or greenish colour, little doubt can be entertained, especially if in addition, auscultation detect signs of the first or second stages of pneumonic inflammation, or of a vomica. It must nevertheless be remembered, that a person, particularly if intemperate in his habits, may have pulmonic inflammation attended with fœtid breath and offensive discoloured expectoration, without any evidence of actual gangrene of the lung; and we have seen a case in which the stench of the breath and expectoration was such as to render the patient's apartment almost insupportable, but which nevertheless terminated favourably; and on examination of the body a considerable time afterwards, no trace whatever of previous disorganization could be detected.

The treatment will obviously consist in supporting the

patient's strength by ammonia, bark, serpentary, opium, wine, porter, and sometimes brandy or gin, and by a good supply of nourishing food.

PNEUMOTHORAX.

By pneumothorax is understood an accumulation of air or gas in the cavity of the pleura. It is sometimes extremely difficult to determine precisely the source of the air so accumulated. Its most obvious as well as most frequent source, is unquestionably the lung of the side so affected, from which it escapes in consequence of a communication being established between the interior of the organ and the pleural sac. This communication may be occasioned by phthisical or gangrenous disorganization of the lung, and consequent rupture or destruction of the pulmonary pleura situated above the disorganized part; it may be produced by a wound, or by rupture of the aircells and pleura, independent of either of these disorganizing processes; or it may be the result of an ulceration of the pleura excited by the presence of pleuritic effusion. The air or gas is said to be in some instances a product of the decomposition of morbid matters deposited within the pleuræ ; and is even supposed to be occasionally, though more rarely, a secretion from the serous membrane itself. That it is most frequently derived from the lung, is proved by repeated dissection, but the other reputed sources are by no means so satisfactorily established; and it must be admitted that a communication with the interior of the lung, sufficiently large to allow the escape of a considerable quantity of air, may exist, without our being able to detect it by the most diligent investigation after death.

On dissection we either find the pleural cavity of the