STETHOSCOPY. 195 



The whole of the left lung is found performing its functions 

 healthfully. Nor is any disease found in the upper portion of the 

 right lung ; but, on searching the lower two thirds of this side, there 

 is found an entii'e absence of all sounds of respiration ; and, under 

 percussion, no normal resonance due to the presence of spongy lung- 

 tissue is heard — the sound is non-resonant. A partial resonance 

 would be dullness ; in this case it is "^a^." 



These data prove the absence of all healthy lung-tissue in the 

 lower two thirds of the right side of the chest. What, then, occupies 

 this region ? The lung solidified by morbid changes may be there ; 

 or it may be displaced by a tumor, or by fluids ; and each of these 

 morbid conditions has nearly the indications mentioned. On care- 

 fully examining the upper limit of flatness of sound, while the patient 

 is sitting or standing, it is found to extend exactly horizontally around 

 the chest. Next, requiring the patient to recline backward, the phy- 

 sician finds the boundary-line of flatness to have changed to two or 

 three inches lower on the front, while upon the back of the chest it 

 will be higher than before ; yet the line is still strictly horizontal. 



The significance of this test is that, though the chest has changed 

 its position, its movable contents, obeying their physical law, tend to 

 preserve a horizontal surface. 



Certain complications may prevent the availability of this " hydro- 

 static test" ; but when found it is infallible, and in this case excludes 

 all of the supposed conditions. 



The diagnosis now is, that the right lung has been compressed into 

 a narrow compass in the upper part of the chest by the gradual accu- 

 mulation of from thirty to forty ounces of fluid ; and this fluid has 

 also so encroached upon the heart as to cause some displacement and 

 to embarrass its action as well as that of the left lung. These condi- 

 tions account fully for the symptoms mentioned, and for the distress 

 of the patient. 



Negatives, exclusions, and probabilities alone are inadmissible ; a 

 diagnosis is required. The examiner may not guess from the symp- 

 toms ; his tests must be objective, and as positive as the laws of 

 physics. They must not fail, for the life of his patient is at stake ; 

 and the treatment to follow will prove his skill, or, may be, his fatal 

 error. If a small hollow needle be pressed through the chest-walls 

 into the suspected region, the outpouring fluid will bring the needed 

 relief and will verify the predictions of the ear by actual sight, weight, 

 and measurement. This case is one of no uncommon occurrence, the 

 treatment almost painless, and very satisfactory as to present relief 

 and the prospect of permanent cure ; the lung may expand to its nor- 

 mal size, and resume its functions healthfully. And the case is one 

 requiring only the ordinary and easier means of diagnosis. 



The acutest ear and the most practiced discernment are required 

 in meeting the difiiculties arising from complications of diseases, and 



