Vocal resonance or weak bronchophony. Moist bronchial or bubbling rales are likely to be heard within and around this space. These signs are not available if the gangrene occur in connection with pneumonitis or tuberculosis; but they serve to establish the diagnosis, taken in connection with the characteristic expectoration, if the affections just named be not associated. If the gangrene be circumscribed, and the patient survive the sloughing and removal by expectoration of the decomposed mass, the cavernous signs may be discovered.

As regards prognosis, if the gangrene be circumscribed and it do not occur under circumstances which are dangerous, irrespective of the gangrene, recovery may take place. The chances of recovery are differently estimated by different writers, which, perhaps, may be accounted for by supposing that the diagnosis of gangrene is not infrequently based on insufficient grounds. It can hardly be doubted that the result is fatal in a large majority of cases. Hæmoptysis sometimes takes place in connection with the separation of the slough or eschar. I have known the hemorrhage to be so abundant as to prove the immediate cause of death. If the gangrene involve the pleura, perforation of the lung takes place, and pleuritis with pneumothorax is developed. These cases probably always end fatally. I have met with two examples.

The treatment of pulmonary gangrene is to be directed more to the system than to the local affection. The affection never occurs under circumstances which render depletion or other debilitating measures appropriate; on the contrary, such measures can hardly fail to be pernicious. Tonic remedies

are indicated, and the sustaining treatment. The diet should be as nutritions as possible, and alcoholic stimulants are to be given with a freedom proportionate to the tendency to failure of the vital powers. The employment of opium, in some form, is important, in order to palliate pain or undue cough, and to allay constitutional irritation. The chlorate of potassa has been sug gested as likely to be useful, from its apparent usefulness in gangrenous affections of the mouth and throat. The tincture of the chloride of iron is suggested by the same analogy. The inhalation of the vapor of turpentine poured upon boiling water is extolled by Skoda as exerting a favorable local effect. Others have attributed a curative influence to the inhalation of tar vapor, creasote, and chlorine.

To diminish the offensive odor of the breath, chlorinated water, or a solution of the permanganate of potassa may be used as a collutory.

PULMONARY EDEMA.

Pulmonary edema is always dependent on other pathological conditions, and is not entitled to be considered as an individual affection. It is, however, an event of not infrequent occurrence, and is important as interfering with the function of respiration, and, in not a few instances, proving the immediate cause of death. The term cedema denotes, in other situations, a dropsical effusion into the areolar tissue; but, in cedema of the lungs, the transudation is primarily and chiefly within the air-cells, the serum also infiltrating the interlobular and intervesicular structure.

An oedematous lobe or lung is increased in volume and weight; it pits on pressure like the integument in ordinary cedema; on section, a purely serous or sero-sanguinolent liquid escapes in abundance, containing but few air bubbles, and, on pressing out the liquid, the mass of the lobe or lung and its weight are found not to be greater than in health, showing the absence of any solid deposit. Microscopical examination shows the pulmonary structure to be intact. More or less oedema of the lungs is frequently found in

post-mortem examinations. It may extend over portions of both lungs, generally, under these circumstances, being situated in the posterior portions, or it may be limited to one lung, in the latter case extending over the whole lung, or confined to one lobe.

The pathological conditions on which it is dependent are various. It is one of the situations of dropsy in cases of degenerative lesions of the kidneys and of acute albuminuria. It is incidental to the pulmonary congestion necessarily induced by cardiac lesions, more especially those which involve mitral obstruction or regurgitation, or both. It occurs in cases in which congestion of the lungs is produced by obstruction of the pulmonary veins from the pressure of an aneurismal tumor. The hypostatic congestion which occurs in low fevers and other diseases in which the blood is impaired, and when patients maintain, for a long time, recumbency on the back, gives rise to it, and, under these circumstances, it is not infrequently the immediate cause of death. It is generally associated with more or less hydrothorax. It may take the place of hydrothorax if the pleural surfaces are united by old adhesions. In a case of general dropsy succeeding scarlatina, the patient dying from interruption of the respiratory function, or apnoea, hydrothorax existed on one side, and the lung of the other side was highly oedematous, the pleural sac, in the latter side, being abolished by universal close adhesions due to an old pleurisy.

The symptoms of oedema are, increased frequency of the respirations with dyspnoea, in proportion to the extent of lung affected, together with more or less cough and serous expectoration, or bronchorrhoea. The displacement of air in the air-cells by liquid, gives rise to dulness or flatness on percussion over a space corresponding to the oedematous portion of lung, and, within this space, the respiratory murmur is lost, or it is feebly bronchial or broncho-vesicular. The vocal resonance may be increased. The presence of liquid in the smaller bronchial tubes is denoted by fine mucous or subcrepitant rales. It is stated that a true crepitant rale may be produced, but this must be extremely rare. The diagnosis is to be based on dulness or flatness on both sides of the chest, associated with moist bronchial rales, pneumonitis being excluded, and the existence of Bright's disease, cardiac lesions, or other causative conditions, being considered.

The treatment must have reference to the circumstances under which it occurs. Occurring in connection with disease of the kidneys, those measures are indicated which are applicable to dropsical effusion in other situations, viz., hydragogue cathartics, diuretics, and sudorifics, selected and regulated according to the circumstances belonging to individual cases. When incidental to disease of the heart, the main reliance is upon revulsive measures, in connection with such remedies as the condition of the heart may claim irrespective of this result. In the cases in which it is dependent on adynamia and an impaired condition of the blood, tonic and sustaining measures are called for. The liability of its occurrence in connection with hypostatic congestion, in fevers and other protracted diseases, accompanied by feebleness of the circulation and depression of the vital powers, renders it an important part of the treatment of these diseases to see that the patient be not allowed to lie constantly in one position. The position of the body should be frequently changed, in order to obviate the gravitation of blood to the dependent portions of the lungs.

CARCINOMA OF LUNG.

Carcinoma affecting the lungs is extremely rare, and is generally developed secondarily, that is, subsequently to carcinoma in other situations. It is pre

sented in two forms. In one form the carcinomatous deposit is infiltrated, replacing the pulmonary structure, or leading to its disintegration; in the other form the point of departure is exterior to the pulmonary organs, either in the pleura, mediastinum, or the bronchial glands. According to Wilks, the primary seat is frequently that last named. The medullary or encephaloid is the variety of intra-thoracic cancer usually met with. Scirrhus in this situation is infrequent, and colloid has been known to occur in a very few instances only.

Infiltrated carcinoma involves at first, and for a considerable period, solidification in proportion to the amount and extent of the deposit. After a time softening and ulceration ensue, and cavities may be produced. Contraction of the affected side takes place prior to the changes just stated. Hemorrhage and gangrene are incidental events, occurring in some cases. symptoms are pain, cough, and expectoration, the latter becoming mucopurulent, and sometimes presenting an appearance of currant jelly. This appearance is somewhat diagnostic.

The

The diagnosis is to be based on the symptoms, taken in connection with the signs of solidification, and sometimes the cavernous signs. The physical evidence is not very distinctive of this affection. Pulmonary tuberculosis and chronic pneumonitis are to be excluded by a careful investigation with reference to the history, as well as the existing symptomatic phenomena. The coexistence of carcinoma in some other situation, or its previous existence, is to be taken into account in arriving at a diagnosis. According to Walshe, pulmonary cancer is especially apt to follow cancerous disease of the testicle.

Or,

When the primary seat is exterior to the lungs, it is presented in the form of nodules, more or less numerous, varying in size from that of a pea to that of an orange, which may be confined to one side, or present in both lungs; the pleural surfaces are sometimes thickly studded with these. it may be in the form of one or more tumors, which attain, in some instances, to a great size, occupying the greater part or the whole of one side (oftener the right), and sometimes encroaching more or less on the other side of the chest. The lungs are displaced, and undergo compression in proportion to the extent of the carcinomatous growth, and the affected side may be more or less dilated. The dilatation, in some cases, is increased by liquid effusion due to coexisting pleuritis. Under these circumstances the affection is liable to be mistaken for empyema or chronic pleuritis. This error has happened to physicians of skill and experience in the physical exploration of the chest. The presence of tumors, great or small, gives rise to dulness or flatness on percussion, with either suppression of the respiratory murmur, or the modification which denotes solidification. The tumors may be so situated as to give rise to symptoms and signs proceeding from pressure on important parts, other than the lungs. The heart may be displaced. The calibre of the trachea or bronchi may be diminished. Aphonia or laryngeal spasm may be induced, if the recurrent nerve be involved. Congestion limited to the upper extremities, head and neck, and subcutaneous cedema, denote obstruction of the superior vena cava. Pressure on the pulmonary veins may give rise to bronchorrhagia and oedema of the lungs. Compres sion of the œsophagus occasions difficulty in the ingestion of food and drinks. These results of pressure on adjacent parts, however, are common to other than carcinomatous tumors, for example aortic aneurisms.

I shall content myself with this brief reference to carcinoma within the chest. For a full consideration of the points involved in the diagnosis, the reader is referred to works which treat in extenso of thoracic affections. In a prac tical view, only the diagnosis of carcinoma claims much consideration.

The affection is hopeless, and the measures of treatment have reference only to the palliation of symptoms, and measures to prolong life. According to Lebert the duration of life varies from one to two years, and, in some cases, death does not take place for several years.

HYDATIDS.

Among the extremely rare affections of the pulmonary organs belong hydatid productions. These may be developed within the lungs, or they have been developed in the liver and made their way through the diaphragm into the pulmonary organs, in the manner in which hepatic abscesses are sometimes evacuated into the bronchial tubes, circumscribed peritonitis and pleuritis taking place, leading to adhesions which prevent the evacuation from taking place into either the peritoneal or pleural sac.

Acephalocysts within the lungs may remain for a variable period latent, that is, giving rise to few or no pulmonary symptoms. Sooner or later, however, they excite inflammation of the surrounding parenchyma and bronchial tubes, and then occasion pain, cough, expectoration, febrile movement, etc. They may be discharged by ulceration into the bronchial tubes, leaving pulmonary cavities. The affection is likely to be mistaken for pulmonary tuberculosis. Microscopical examination of the matter expectorated may show the hooklets of echinococci, and without this demonstration the diagnosis is impracticable. The question as to the primary seat of the cysts is to be settled by the previous history, which, if they come from the liver, will show the existence of hepatic trouble prior to the occurrence of pulmonary symptoms.

The presence of hydatids in the lungs always involves great danger. The danger is greater when they are derived from the liver than when they are developed within the lungs. Fuller estimates that of cases of the latter, recovery takes place in the proportion of one-half. There is no special plan of treatment. Palliative and sustaining measures are to be adapted to the circumstances of individual cases.

CHAPTER IX.

Affections of the Larynx and Trachea-Points relating to the Anatomy and Physiology of the Larynx which are involved in the consideration of Diseases in this situation-Acute Ordinary Laryngitis-Anatomical Characters-Clinical History-Pathological Character-Causation-Diagnosis-Prognosis-Treatment-Subacute Laryngitis — Chronic Laryngitis - Laryngitis with Exudation of Lymph-Clinical History-Pathological Character-Causation -Diagnosis-Prognosis-Treatment-Edema of the Glottis-Spasm of the Glottis-Nervous Aphonia-Morbid Growths.

IMPORTANT diseases affecting the respiratory apparatus are seated above the chest, viz., in the larynx and trachea. Diseases of the larynx frequently involve the trachea, but it is rare for the latter to be affected without the former, and it will suffice to consider tracheal affections incidentally in treating of those of the larynx.

Certain anatomical and physiological points pertaining to the larynx are to be kept in mind with a view to a clear apprehension of the diseases in this situation. The larynx is composed of a collection of cartilages, viz., the

cricoid, thyroid, arytenoid, and the epiglottis. The latter was formerly supposed to be essential as a protection against the entrance of food and drink into the laryngeal cavity during the act of deglutition. The removal of this appendage, however, in inferior animals has shown that its loss does not occasion serious inconvenience. It has occurred to me to meet with a hospital case in which this part was completely destroyed by syphilitic ulceration, as determined by the touch and the laryngoscope. The patient, a young female, was for some time under my observation at Bellevue Hospital. So long as ulceration existed, there was considerable difficulty arising from spasm of the glottis excited by contact with food and drink, and deglutition was performed with the least annoyance while the patient was lying on the back. But after the ulceration had healed, the difficulty nearly ceased, liquids and solids being swallowed without much inconvenience. The quality of the voice underwent some change, and the patient stated that she had not the power of producing notes in singing as before.

The small size of the rima glottidis is an important point in connection with diseases here stated. In the adult male, after death, it is a triangular space an inch in length, and, at the base, about a quarter of an inch in width, the size being still smaller in the female and child. The dimensions, however, vary with the two respiratory acts. When examined in a living animal, the vocal chords are found to separate widely in inspiration and return in expiration, forming the respiratory movements of the glottis. And these movements are found to take place from a reflex influence communicated through the recurrent nerves. These points are of interest and importance in their practical applications.

Other movements of the muscles of the larynx are produced by volition in the acts of speaking. The larynx being the seat of the voice, modifications of vocal sound constitute important symptomatic phenomena of disease. The experiments of Bernard have shown that in producing the movements concerned in phonation, the will acts through branches of the spinal accessory contained in the recurrent laryngeal nerves. The laryngeal muscles are subject to spasm and paralysis.

The solidity of the walls of the larynx is an important point in connection with certain affections. The cricoid and thyroid cartilages do not readily yield to internal pressure, and hence arises obstruction from the presence of morbid products which encroach upon the small space between the vocal chords. Another point to which reference will be made is the abundance of loose areolar tissue beneath the mucous membrane, especially above the vocal chords. This is much more marked in the adult than in the child, a fact which will serve to account for certain differences as regards the effects of disease during and after infantile life.

Of the affections of the larynx, those involving inflammation will be first considered. Inflammation here may be of an ordinary character, that is, not distinguished by any unusual features save those which are incident to the situation of the affected mucous membrane. On the other hand, it may be of an extraordinary or unusual character, viz., accompanied by an exudation of lymph. The latter will be considered under a separate head. Ordinary inflammation may be either acute, subacute, or chronic. These three varieties are to be considered separately. The appropriate name for inflammation affecting the larynx is laryngitis. This name should take the place of the terms angina and cynanche which were formerly in vogue, but now rarely used. The term croup is applied to laryngitis with the exudation of lymph, and also to cases of ordinary laryngitis and a non-inflammatory affection, viz., spasm of the glottis, occurring in children. The first of these affections embraced by the term, is sometimes distinguished as true croup, while the