A HISTORY OF SCIENCE 

 BOOK IV 



MODERN DEVELOPMENT OF THE CHEMICAL 

 AND BIOLOGICAL SCIENCES 



AS regards chronology, the epoch covered in the 

 /~\ present volume is identical with that viewed in 

 the preceding one. But now as regards subject matter 

 we pass on to those diverse phases of the physical 

 world which are the field of the chemist, and to those 

 yet more intricate processes which have to do with liv- 

 ing organisms. So radical are the changes here that 

 we seem to be entering new worlds; and yet, here as 

 before, there are intimations of the new discoveries 

 away back in the Greek days. The solution of the 

 problem of respiration will remind us that Anaxagoras 

 half guessed the secret ; and in those diversified studies 

 which tell us of the Daltonian atom in its wonderful 

 transmutations, we shall be reminded again of the 

 Clazomenian philosopher and his successor Democritus. 

 Yet we should press the analogy much too far were 

 we to intimate that the Greek of the elder day or any 



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