130 EESPIEATION. 



whicli exists between a part locally affected and tlie system at 

 large. An injury inflicted upon the foot will not unfrequently 

 give rise to violent commotion of the respiratory organs ; so 

 that rapid breathing, when the animal stands at rest, accom- 

 panied as it generally is with other symptoms indicative of 

 violent disturbance within the svstem, is not at all times to be 

 regarded as noting the existence of acute disease within the 

 lungs. As a general rule, however, when the lungs are directly 

 affected, there are certain sounds associated with the breathing 

 of the patient, which betoken whether the disturbance be 

 primary to these organs or not. The reader will find the 

 nature of these sounds, and their peculiarities treated upon, in 

 the section devoted to those diseases incidental to the respira- 

 tory organs. A respiration is the result of a double act — that 

 is, it consists of one inspiration and one expiration. The 

 average number of respirations of a healthy horse per minute 

 are about twelve. As a general rule, the pulse of the 

 animal will beat three times during the production of one 

 respiration. The average now given, and the relation of the 

 respiratory act to the pulse, must be understood as strictly 

 referring to the animal when in the stable, and free from all 

 excitement. 



When the lungs are diseased, the respirations will at times 

 reach from fifty to sixty per minute, or even more, in short, a 

 very exact limit cannot be stated ; they should always be noted, 

 however, with care. To an experienced observer, the manner 

 in which the act of breathing is performed is significant in the 

 extreme. In Pleurodynia and Pleurisy the act is limited and 

 constrained, attended with a peculiar tremor of the muscles of 

 the sides, a pinched appearance of the alsB of the nostrils, a 

 slight arching of the back, and if the sides are pinched or 

 pressed upon, a peculiar grunt is emitted. In Tetanus the 



