OF ORGANIC NATURE. 27 



certainty that there is left in no one of our bodies at 

 the present moment a millionth part of the matter 

 of which they were originally formed ! We have seen, 

 again, that not only is the living matter derived from 

 the inorganic world, but that the forces of that matter 

 are all of them correlative with and convertible into 

 those of inorganic nature. 



This, for our present purposes, is the best view of 

 the present condition of organic nature which I can 

 lay before you : it gives you the great outlines of a 

 vast picture, which you must fill up by your own 

 study. 



In the next lecture I shall endeavour in the same 

 way to go back into the past, and to sketch in the 

 same broad manner the history of life in epochs pre- 

 ceding our own. 



