394 MATER i A MEDIC A AND THERAPEUTICS. 



increased activity gives rise to enlargement or hypertrophy of 

 the organ, and what is known as compensation is the result. 

 This great natural method of prevention or recovery hy over- 

 coming the cause of disorder is well seen in heart disease, and in 

 enlargement of one kidney when the other is diseased. 



Instead of themselves meeting extraordinary circumstances 

 "by extraordinary activity, many organs are provided with regula- 

 ting mechanisms, hy which they can throw them off or escape from 

 them, that is, expel the cause of disorder. The stomach 

 rejects a heavy or improper meal ; the heart can, to 

 some extent, relieve itself of excessive peripheral resistance 

 in systole, through the depressor mechanism ; and the hody 

 heat is elaborately regulated hy various nervous arrangements. 



Thirdly, the work of one organ may sometimes he under- 

 taken by another organ, which thus removes the effects of the 

 disorder. This is called vicarious compensation, and is well 

 seen at work between the kidney and other excretory 

 organs. 



Fourthly, even when disease and anatomical change have 

 actually occurred, the body possesses means of recovery of 

 the nature of repair, which is associated with nutritive activity 

 and frequently with the inflammatory process. 



These considerations teach us that just as our organs and 

 functions continue normal, like everything else in nature, in 

 obedience to the laws under which they have reached their 

 present form, so, if they have become deranged by unusual 

 influences, they will return to the normal when such abnormal 

 influences have been overcome or removed. 



5. Therapeutics. The following are the four foundations 

 of rational therapeutics. (1) Inasmuch as the organs act in 

 obedience to natural forces in and around us; (2) since we 

 possess the power of controlling these forces ; (3) since dis- 

 order and disease are but the physiological phenomena, or the 

 anatomical results of the disturbing action of ordinary or 

 extraordinary influences; and (4) since the functions of the 

 organs, and, it may be, even their anatomical state will return 

 to the normal, if the influences become normal : it logically 

 follows that therapeutics as a science consists in bending to our 

 will the numerous natural forces which affect the human body, 

 or in counteracting or neutralising their effects by other forces, 

 until, in either case nature returns to the normal. To handle, 

 as it were, the natural influences which surround us in such 

 a manner as to effect this change on the functions of the 

 body, is called treating the disorders or diseases of it. It is with 

 this meaning that we shall speak of rational treatment. 



Now it is evident that treatment may be of many kinds : 



