406 



THE CIRCULATION. 



body, there is not enough blood in that part, while there will be an 

 excess in other parts. Thus, if the horse is exposed to a cold wind or 

 is chilled by a current of air striking the body, the blood will be 

 forced from its surface to the internal organs, accumulating where 

 there is most freedom for it, or where it is Weakest ; usually in, the 

 lungs and surrounding parts, kidneys, bowels, and sometimes in the 

 feet, the first indication of which would be a shivering fit, followed 



by fever. Now, it is ev- 

 ident that the object 

 should be, when there is 

 such disturbance, to 

 equalize the circulation 

 again, or forbe it back to 

 its natural channels as 

 ~ quickly as possible, and 

 that treatment by which 

 this can be done most 

 easily and quickly will 

 be^the best. The cir- 

 culation is really con- 

 trolled by the nervous 

 system. If the nervous 

 system is from any cause 

 weakened, so that it is 

 unable to act with the 



a, a, Veins; b, b, b, Arteries, the capillaries being usual vigor, there is less 

 between. .... .... 



ability to resist-the in- 

 fluence of disturbing changes, and the horse is, as it is termed, more 

 liable to take cold, which means a disturbance of the circulation. 



Hence a horse, when warm and exhausted after a drive, if given 

 a little too much cold water, would be liable to have colic, founder, 

 etc. ; or if allowed to stand in a cold current of air, to have an at- 

 tack of pneumonia, or sortie other indication of vascular disturbance 

 before referred to, which would be scarcely felt if cool, and the nerv- 

 ous system in a vigorous condition. 



It is evident also that the quality of blood being dependent upon 

 the food taken, and the condition of the air breathed, it is necessary 

 that the food should be clean" and of good quality. No moldy grain, 

 hay, or other food unfitted for proper nutrition, should be given, and 

 the stable should be well ventilated with pure air at all times, and 

 all poisonous gases, particularly the ammonia which is formed from 

 the urine, should be allowed free egress from the stable, as the animal 



Fig. 696. — Web of Frog's Foot Stretching between Two 



Toes, Showing the Blood-vessels and their 



Anastomoses. 



