ORIGIN OF DISEASE AND THE GERM THEORY. 153 



similar cases, the fecal accumulation excites the mucous mem- 

 branes and the muscular coat of the intestines, and the additional 

 activity brings with it, according to the view above expressed, 

 a rise of temperature, and other associates of work. When, 

 however, the bowels are relieved, this stimulation is no longer 

 kept up, and the result is that the temperature falls. 



The ready response of the temperature of a child or of a 

 patient convalescing from febrile conditions to changed circum- 

 stances is well known. 



Again, the action of some chemical compounds serves to 

 illustrate the association of vital processes above mentioned. 

 For instance, the administration of nicotine produces accelera- 

 tion of the heart's action, perspiration, and diarrhoea, while 

 morphine, on the other hand, causes a slowing of the pulse, a 

 dry skin, constipation, and sleep. 



It may very readily be seen that the associates of rest are the 

 counterparts of those of work ; but we must not forget that a state 

 of rest may vary from that of simple repose to the pronounced 

 rest of sleep, or hibernation. Now it is well known that if a 

 man or an animal abstains from taking physical exercise, con- 

 stipation very often results ; and it is also to be noted that if 

 one or more of the associates of work are kept in action, sleep 

 is not to be obtained. For example, when too hot or greatly 

 excited from any cause, we cannot sleep. 



As we have pointed out above, there is apparently an associa- 

 tion of certain vital processes, which are concerned in action, 

 so that if one, or a fortiori, if more than one, be aroused, 

 the others are generally also induced. There is also another 

 association of vital processes called rest, and if some of these 

 are exhibited, then, in the general way, the others will also be 

 more or less strongly apparent. If we compare these two, work 

 and rest, together, we meet with many striking points. Further, 

 if muscles are freely exercised, they may become hypertrophied ; 

 while, if excessive rest be allowed, they become atrophied. This 

 same rule applies also to other tissues and organs. The two 

 states, rest and work, ought to be alternated with each other. 

 It is most important that this rhythm of waste and repair should 

 be attended to, for otherwise the muscle, the limb, or the 

 organism, as the case may be, must suffer when waste exceeds 

 repair. 



