DISEASES OF THE HEART AND BLOOD, ETC. 375 



of Chapter II, the beats of the pulse simply indicate so many 

 impulsions of the blood from the heart. !N'ow, there can be 

 no considerable excitement of the system, whether from ex- 

 ercise, intense emotion, or disease, without causing a corre- 

 spondingly increased action of the heart. This is indexed by 

 the pulse, and thus the presence of disease is readily detected, 

 and its course traced throughout all its developments. 



The pulse may be discovered and counted in several places 

 on the horse's body, but nowhere else is it so easily found 

 as upon the underside of the lower jaw-bone, at the point 

 indicated in our description of the foregoing cut. Here the 

 submaxillary artery passes over the edge of the bone, and 

 feels like a small cord under the skin. By pressing the 

 fingers upon it steadily, the pulsations may be felt pushing 

 their way along at the rate of about thirty-fiv6 per minute 

 in the farmer's horse, although some fine breeds average as 

 much as forty, or even more, when in perfect health. This 

 is what writers refer to when they speak of the standard 

 pulse. The great advantage of resorting to the submaxillary 

 artery to find the pulse is this: that here pressure upon the 

 hard bone beneath enables one to determine, not merely the 

 rapidity of the pulse, but also its strength and other charac- 

 teristics. 



Fifty beats to the minute, when the horse is not laboring 

 under muscular or nervous agitation, constitutes a decidedly 

 diseased pulse, and seventy or eighty betrays a most fearful 

 state of excitement. Such is the case in blind staggers, for 

 instance. As high a pulse as one hundred to the minute is 

 recorded by English veterinarians ; but the farm horse of 

 this country rarely shows one above eighty, which is quite 

 sufficient to soon wear out his vital energies. In inflamma- 

 tion of the lungs or bowels, seventy per minute is about the 

 maximum attained in the great majority of cases. 



In health the pulsations are slow and soft, making an im- 

 pression, truly, that is readily recognized when the pressuie 

 of the finger is applied, but not hard and tense by any means. 

 But as fever and inflammation come on, the vein becomes 



