The discovery of cancer or of aneurism elsewhere, in situations where their nature is more easily recognized, or signs of disease of the heart, would give significance to symptoms otherwise anomalous : no reliance can be placed on the absence of what is called the " malignant aspect," because the color of the face is so liable to be altered by the condition of the lungs ; interference with the proper aeration of the blood necessarily produces a dusky hue.
Nodules of encephaloid disease may cause modifications in percussion raw nance, and in the character of the breath-sound, or they may give rise to bronchial secretion and moist sound ; and most frequently the latter is the only evidence of disease. We can do no more than satisfy ourselves that the balance of evidence is against the existence of phthiais as its cause. Scirrhas, perhaps, gives rise to more important changes in the breathing and vocal resonance, and the physical signs are very like those caused by a vomica, while the condition of the opposite lung is unlike that which is produced by tuber cular deposit, and the general symptoms do not point to such an advanced condition of phthiais as implies the formation of a cavity. Sometimes the appearance of peculiar expectoration, which has been compared to thin cur rant-jelly, gives an assurance of the true character of the disease; but it must be confessed that very little can be done in making out the diagnosis of such cases.
Tumors at the root of the lungs are more easily recognised when the dis ease has made some progress ; in their early stage there is nothing to point out their existence. As soon as they are of sufficient size to produce pres sure on the bronchi, there will be irritation, probably secretion, and fits of dyspncea, closely resembling asthma ; of still larger size, they are apt to cause dysphagia, or to interrupt the current of the circulation; and now the patient find out that in one posture he is more liable to suffer than in another. the tumor has attained a certain magnitude there is dulness, not per ceptible on gentle percussion, but brought out by a firm stroke, most marked near the sternum, and not to be detected in the axilla, or towards the side of the chest. The breathing is generally weaker, with prolonged expiration, heard at a distance : the sounds of the heart are transmitted loudly over the seat of the tumor, and even beyond it. The patient perhaps breathes in a
wheezing manner with considerable labor, or the respiration may be obstructed to nearly the same extent as it is in laryngitis; the cough is often weak and powerless, like that of emphysema, but has more of a paroxysmal character, and sometimes a loud brassy clang : a fit of coughing very generally terminate* with a raucous inspiration. In many of these respects the analogy to gitis is very striking, and the most marked difference between the two when the obstruction is in the larynx itself, the voice is either hoarse or de stroyed, while when it is lower down in the trachea, the voice is scarcely altered in tone ; it is only deficient in force.
The interruption to the circulation caused by the tumor may at once lead no to infer its existence : it presses upon, or even surrounds and incloses the superior vena cave, in consequence of which, tortuous veins begin to develop themselves over the chest and abdomen, and the blood finds its way by a back ward current into some pervious channel ; sooner or later this venous obstruc tion gives rise to oedema, which is then limited, in a remarkable manner, to the upper half of the body. This happens chiefly with malignant growth; wheil aneurism exists additional signs are sometimes derived from the arterial cir culation: the force of the current is diminished in some one or more of the arteries, causing, perhaps, a notable difference between the two radials at the wrist ; or both alike to be almost imperceptible, while the heart's action is very generally, but not always, increased : a bruit may be heard in some unusual part of the chest, while there is none at the heart, or it may be heard loudly at both, and be almost inaudible at intermediate points. Sometimes, again, the ordinary systole of the heart is heard unusually loud at some particular point, and this may be regarded as the effect of aneurism, because the sound has a knocking or jogging character, which is only 'preliminary to a similar impulse being felt, when the disease has approached nearer to the surface.