THE CAUSATION OF DISEASE. 33 



of the great difference of the E of different occupations. For 

 every occupation moulds the individual in a special and peculiar 

 manner, so that in many instances we can say at once what is 

 his particular calling, whether he be soldier, sailor, navvy, 

 groom, policeman, or what not. The E of every trade or pro- 

 fession or calling is, in fact, different. It would he tedious to 

 mention a tithe of them. Among manual workers there is a 

 great difference in respect of the muscles acted upon. Thus the 

 muscular action is different in the farm-labourer, mason, smith, 

 miner, and the workers in the finer kinds of handicrafts; it differs 

 both in respect of the particular muscles acted upon and as to 

 the kind of muscular action. With some the work is long 

 continued, with others it consists of gigantic spasmodic efforts ; 

 sometimes the individual remains stationary — standing, sitting, 

 or even lying; sometimes he moves about, and the effect is 

 very different in the different cases. 



Again, the nature of the atmosphere differs enormously : 

 bakers, miners, masons, and hundreds of other kinds of workers 

 are compelled by the very nature of their calling to breathe an 

 atmosphere laden with, solid particles. Some, such as stokers, 

 are confined in heated atmospheres, others are exposed to 

 repeated draughts, while others, again, are much in the open 

 air, whether on land or sea. And apart from this diversity in 

 the physical E, there is a similar wide difference in the mental E. 

 Each profession or calling impresses and moulds the mind in a 

 particular way, and did we possess the proper analytic power, 

 we should be struck with the different mental states of the 

 members of different professions. 



It is not possible to analyse the external E, mental and phy- 

 sical, of each of the many callings which go to build up our 

 complex social organism ; nor is it necessary, my sole wish 

 being to bring home to the readers mind the comprehensive 

 nature of that which we have termed the external-body-E, and 

 to show how infinitely complex and diverse it is. It is neces- 

 sary to take a careful note of this diversity, for, as we shall 

 see, it tends to render perfect adaptation impossible. In 

 order to attain perfect adaptation, several generations must be 

 exposed to an E more or less similar; but if one genera- 

 tion follows one occupation, and the succeeding generation 



P 



