532 PERCUSSION. 



Sheep. In employing percussion over the chest of the 

 sheep, the following differences may be noticed: 1st, The 

 resonance is clearer over the 5th and 6th ribs in the lower 

 region of the left side, as a result of the heart being com- 

 pletely covered by the anterior lobe of the left lung. 2nd, 

 The pulmonary resonance maintains its clearness and depth 

 more posteriorly than in the cow, in consequence of the 

 anatomical arrangement of the diaphragm already referred 

 to. Thus, in the superior region, the pulmonary sound be- 

 comes less clear over the llth, though it may be detected as 

 far as the 12th or 13th; in the median region it diminishes 

 from the 8th to the llth, where it is lost, while in the lower 

 region it is gradually feebler behind the 7th as far as the 

 10th, where it is replaced by dulness. On the right side 

 posteriorly, the resonance of the abdominal viscera is not so 

 likely to interfere with the proper appreciation of that of the 

 lung. 



Pig. When this animal is emaciated, it may afford satis- 

 factory indications on percussion. The resonance is deepest 

 on either side, close behind the shoulder in the median 

 region. From this it gradually diminishes to the level of 

 the attachment of their diaphragm. In very young or lean 

 subjects the first and second ribs may be examined in front 

 of the shoulder, and will afford a clear resonance. 



Dog. In ordinary cases the resonance elicited on percus- 

 sion of the chest in the dog is especially clear. In the superior 

 region it is well marked behind the shoulder, increases as 

 far as the 7th rib, and from this diminishes to the 12th; be- 

 tween the two last-named ribs the strokes should be very 

 light, made with the median finger only, to avoid the pro- 

 duction of abdominal sound. In the median regions the 

 sound elicited is very clear from the 3rd to the 7th rib, 

 from which it again diminishes to the last. In the lower 



