AMERICAN PREFACE 



TO THE 



INTERNATIONAL SCIENTIFIC SEEIES. 



The rapid development of science in the present age, 

 and the increasing public interest in its results, make it 

 desirable that the most efficient measures should be adopted 

 to elevate the character of its popular literature. The ten- 

 dency of careless and unscrupulous book-makers to cater to 

 public ignorance and love of the marvellous, and to foist their 

 crude productions upon those who are too little instructed to 

 judge of their real quality, has hitherto been so strong as to 

 cast discredit upon the idea of " popular science." It is 

 highly important to counteract this evil tendency by fur- 

 nishing the public with popular scientific books of a superior 

 character. The publication of the present volume is the first 

 step in carrying out a systematic enterprise of this kind. It 

 initiates a series of such works on a wide range of scientific 

 subjects, to be prepared by the leading thinkers of different 

 countries, and known as the "International Scientific 

 Series." 



