166 The Farmer's Veterinary Adviser. 



horses this murmur is absent and replaced by the sound? 

 of the heart. Between the upper and middle thirds of the 

 chest it mingles with the blowing sound anteriorly, but is 

 unaccompanied by that over the few last ribs. Percussion 

 consists in drawing out the resonance of any part by strik- 

 ing it gentle taps with a hard object, the blows falling per- 

 pendicularly to its surface, and of a force proportioned to 

 the depth of the organ it is meant to sound. Thus, for tho 

 surface, the gentlest taps with the tip of. the finger are 

 wanted, while for the centre of the chest in large animals, 

 the closed fist may be advantageously used. For inter- 

 mediate depths the four fingers and thumb may be brought 

 together, ia a straight line at their tips, and the surface 

 tapped with this. When a cavity, enclosed by a hard 

 bony surface, such as the nose, is being sounded, it is well 

 enough to tap this direct, but if the surface is soft, as in 

 the chest of fat and fleshy animals, a hard, sohd body 

 should be pressed firmly upon it and the taps delivered 

 upon this. As the different parts of the right hand ma^ 

 be used for delivering the taps, so may the two middle fiji- 

 gers of the left hand be employed to compress the soft 

 parts and receive them. The front of the fingers should 

 be apphed against the surface and the hard bony backs 

 turned out to receive the taps. If percussion is made over 

 a hollow space, like the nose or windpipe, the sound is 

 drum-Uke ; if over an open, spongy tissue, like the lung, it 

 is much less so but stiU fuU and clear, but if over a soUd 

 body, like the thigh, it is duU, dead, or quite wanting in 

 resonance. Behind the left elbow such dull sound is met 

 with in the horse and, to a less extent, in cattle ; and on 

 the last ribs on the right side ia cattle, sheep and pigs a 

 similar dullness is found in accordance with the position 

 of the hver. Any increase, diminution or loss of reso- 

 nance over particular parts thus becomes of great value aa 

 indicating the healthy or unnatural state of the parts. 

 But the observer must learn this matter by experience on 

 tho healthy and diseased. These hints are merely thrown 

 out to make what will follow intelligible. 



