126 DISEASES OF THE PARENCHYMA OF THE LUNG. 



and in a permanent inspiratory condition. The augmented contractility 

 of the hypertrophied muscles of inspiration may contribute in some de- 

 gree to this perpetual condition of dilatation, but it no doubt mainly 

 depends upon the disease of the costal cartilages so often referred to. 



Inspection, in many cases of emphysema, further reveals that, with 

 every violent cough, a tumor projects through the upper aperture of the 

 thorax at the side of the neck, which disappears immediately upon the 

 cessation of the coughing-fit. I have recently satisfied myself that this 

 tumor very rarely consists of the apex of the lung, which, with the 

 pleura, has been driven into the space between the first rib and the 

 neck by the violent pressure of the diaphragm, which, as it were, makes 

 the chest too smalL In the great majority of cases, these tumors are 

 formed by enormous enlargements of the sinus of the jugular veins 

 which fill up during the cough and empty themselves again when it 

 ceases. 



Finally, upon inspection, and, still better, upon palpation, we can 

 perceive a strong concussion of the epigastrium, which is synchronous 

 with the pulse, and which extends to the lower part of the sternum 

 and of the adjoining ribs. This concussion has been usually ascribed to 

 the shock of the apex of the heart, displaced toward the middle line of 

 the body, but I agree with Bamberger^ that such displacement is 

 neither proved by facts nor even physically possible. This concussion 

 of the epigastrium is not directly dependent upon emphysema, but 

 is due to hypertrophy of the right heart, which complicates that dis- 

 ease, and it is found in all considerable cases of hypertrophy, espe- 

 cially of the right heart without emphysema. (See Hypertrophy of 

 Heart.) Even when the heart of an emphysematous patient has be- 

 come considerably enlarged, the shock of its apex is imperceptible, the 

 lung having become interposed between it and the thoracic wall. 

 Sometimes, however, besides the concussion of the epigastrium, a feeble 

 heart-shock is perceptible at a point farther downward and outward 

 than is normal. That the apex is displaced downward, is simply owing 

 to the depression of the diaphragm, upon which it rests. But it is not 

 only the apex of the heart, but its base too, which rests upon the dia- 

 phragm, and, indeed, upon the very part of it which descends the 

 furthest in cases of its abnormal depression (farther, at least, than the 

 point upon which the apex lies). Hence, as a natural consequence of 

 depression of the diaphragm in emphysema, the oblique position of th.' 

 heart becomes more horizontal, and its apex lies farther out. 



Percussion affords an almost certain basis for diagnosis where em 

 physema is of considerable extent. However, we must not expect the 

 sound to be unusually loud or full in all cases, as, if the resistance of 

 the thoracic wall be augmented, even though the vital capacity of the 



