SIGNS AND SYMPTOMS OF DISEASE 147 



All the above described conditions of the pulse, which can be appre- 

 ciated without the aid of any instruments, convey to the mind of the 

 expert certain ideas as to the state of the animal's system or of some 

 particular part or organ. The frequent pulse, for instance — that is, a pulse 

 which beats more frequently than the standard number of 40 in the 

 minute, — in the horse indicates some degree of excitation in the circulatory 

 system, which may depend on a variety of causes — exercise, a sudden 

 alarm, the mere entrance of a stranger or a strange animal, may increase 

 the frequency of the pulse within certain limits; but when in the horse the 

 beats reach to 50 or 60 in the minute, or above, fever is obviously indicated. 



Fig. 493.— Feeling the Pulse 



A very frequent pulse may, however, be associated with extreme debility; 

 but in addition to the rapidity of the pulse in such circumstances there 

 will be an important change in its character. 



An infrequent pulse is found in diseases of the heart or brain, and in 

 such cases the pulse is often intermittent, a condition which is extremely 

 characteristic and easily recognized; a number of regular beats being fol- 

 lowed by a period of rest, and then succeeded by another sequence of 

 regular beats. 



Quick pulse as distinguished from frequent pulse is more easily dis- 

 covered by the sphygmograph than by the finger. It depends upon the 

 sudden contraction of the ventricle; the expansion of the artery con- 

 sequently occupies less time than in the healthy pulse, although by cal- 

 culating the number of beats during a given period the quick pulse may be 

 found to be also less frequent than the normal. The quick pulse would 

 usually be taken to indicate excess in irritability of the muscular structure 

 of the heart. 



