THE RECOIL OF MAN'S INFLUENCE 



513 



returned to him again, when the sweat of his brow was repaid 

 a thousand-fold in the health of his body. 



Man drained the marshes and the stagnant pools and so 

 destroyed the Mosquitoes, which could multiply only there, 

 and so he destroyed the only transmitters of the tiny Plas- 

 modium of the human blood, and malaria or ague was no more. 

 Man, Marshes, Mosquitoes, Malaria steps and stages of a 

 progress which, starting with man, returns through the 

 worlds of inanimate and animate nature, to heap blessings 

 on his head. 



AN EFFECT 



OF 



CULTIVATION 



OF THE 



SOIL 



RESULT 



OF A 



CHANCE 

 Q^ INTRODUCTION 



GO 



ACCOMPANIMENT 



OF 



CIVILIZATION 



\ 



\ 



Fig. 90. Diagrammatic representation of Recoils on man's health, due to different 

 types of his interference with animal life. 



RECOILS ON MAN'S PROSPERITY 



But even where man has not been affected in his own 

 health, the influences he has set a-rolling have recoiled upon 

 his well-being. The draining of the marshes affords a case 

 in point. Man acted unwittingly, for not till long after the 



p 33 



