HORSE-BACK RIDING, 67 



exercises in which he indulges, will all strongly 

 modify the effect produced on the system. 



The results derived from horse-back riding are 

 therefore dependent upon and modified by the pace, 

 the duration and character of the exercise, the nature 

 and gait of the horse, the method of riding, and 

 habits of the rider. 



General Diseases. 



I. Morbid states of the blood. 



a. Plethora (excessive fulness of blood). — ;This con- 

 dition, seemingly intermediate between health and 

 disease, consists in either an excessive amount of 

 blood or a superabundance of red globules — the 

 quantity being normal — that is an over-richness. 



It is recognized by the redness of the face, caused 

 by the distension of the capillaries, especially those 

 of the cheeks, lips, and mucous membranes, by 

 the strong resistant pulse and the turgid condition 

 of the veins. It is often accompanied by loss of 

 appetite, constipation, a tendency to hemorrhages 

 and congestions, and a state of indolence and lassi- 

 tude. Its causes are to be found in, first, a too great 

 activity of the nutritive functions, aided by too free 

 a mode of living, and, second, in the want of sufficient 

 exercise. 



While physicians are at variance respecting the 

 special treatment to be adopted in these cases, they 



