MAN AND NATURE. 265 



the completeness of the picture, and to a right compre- 

 hension of the influences which this new element of 

 human life has had on the physical conditions of the 

 earth's surface. To the animal instincts which before 

 had rule in the world we now find added the higher 

 faculty of intelligent design of mental superinduced 

 on bodily force. This is the subject with which we are 

 here more directly concerned. We are called upon to 

 indicate the extent, or what may better perhaps be 

 termed the limits, of Man's power over the conditions 

 of the natural world around him ; and then to show 

 what he has already done, or may attain hereafter, in 

 effect of this power. We desire the more to mark 

 clearly the several points of the argument, since the 

 want of such method is the defect which will be most 

 felt by the readers of the volume before us. 



First, then, what is the extent, and what are the 

 limits, of human power over the earth we inhabit ? 

 The simplest division of this large question is that 

 which regards the influence of Man, severally, upon 

 the inorganic elements around him, and upon matter 

 organised into animal and vegetable life. There is close 

 inter-relation between these objects, as will at once be 

 obvious ; but, for the sake of clearness, they may better 

 be regarded separately ; and in such division the rela- 

 tion of Man to inorganic existence, whether of matter 

 or force, is that which comes first into view. His in- 

 fluence, as the head of the living creation, on other 

 forms and attributes of life, will be best considered in 

 sequel to the former. 



The atmosphere, the waters, and the superficial crust 



