Preface to the English Edition 



These are the essential qualities of popu- 

 larisation. 



I have endeavoured to make them those of 

 my work. At the same time I have tried to 

 defend the mind of the reader against a species 

 of scientific bluff which is, no doubt, rampant 

 elsewhere than in France, and which consists 

 in representing scientists as magicians who dis- 

 pose of the physical world at will. No day 

 passes without some great discovery being 

 announced. We must teach distrust in these 

 marvels which are boomed so loudly and gain a 

 hearing for voices which are more discreet and 

 thoughtful. 



Such is the end I have kept in view in this 

 book. I feel highly honoured to see it received 

 in a country which has done so much for science. 

 I hope my English readers will reap some benefit 

 from the general ideas expressed in it, and from 

 the directions for the scientific spirit which I set 

 forth, 



L HOULLEVIGUE. 



XIX 



