110 CHAPTEE 11. 



211. Cause of Pulsation. 



The pulse is the beating of the arteries produced by the wave of the 

 blood propelled into them by each contraction of the heart. The sensa- 

 tion which the fingers perceive, when placed over a superficial artery, 

 indicates tne rapidity, force and regularity of the heart's action, and also 

 the relative quantity of blood flowing through the artery. 



As the volume of blood passing through the arteries, when the horse 

 is in a state of good health, is considerable, the pulse is firm and regular. 

 It is, however, greatly increased in frequency during any exertion. 



212. Number of pulsations per minute. 



The range of pulsation per minute in an adult healthy horse, the tem- 

 perature of the air being 60, is from thirty-four to thirty-eight ; and 

 instances are not wanting of healthy pulses being as low as thirty and as 

 high as forty. 



The pulse in young subjects is generally quicker than in aged horses. 

 It is also usually slower in low than in well bred animals. 



213. Taking the Pulse. 



The most convenient places for taking the pulse are the submaxillary, 

 the radial, the temporal, the metatarsal, and the plantar arteries. 



The slightest excitement, especially when a horse is sick, will cause an 

 alteration in the pulse. To ascertain, therefore, the true character of the 

 pulse, both with reference to tone and number, the animal should be 

 approached very quietly, and should be soothed for a minute or two, 

 before the finger is applied to the artery. 



The fore and middle finger should be placed on the artery in a trans- 

 verse direction. If it is placed obliquely, the impression will be erroneous 

 as to the true character of the beat. 



214. Irregularities of the Pulse. 



A regular pulse with proportionate fulness is the best criterion of 

 health. Irregularity usually arises from irritability or debility of the 

 system. 



A strong and full pulse is present during health under any temporary 

 excitement ; but this character is seldom found to accompany any morbid 

 state, into which the animal may fall. The full pulse, which often accom- 

 panies disease, has always some vibratory hardness in it. 



The intermittent pulse. A pulse is said to be intermittent, when it 

 beats two, three, or four times regularly, and then ceases for a period of 

 time equal to two or three beats, before it goes again. 



Irregularity in strength. The pulse may beat with natural force two 

 or three times in succession, and then the next beat or two may be feeble, 

 and afterwards it may become strong again, and so on. 



Intermittent and irregular. The pulse may be both intermittent as to 

 time and also irregular as to tone. 



