36 PASTEUR 



the finest crystals, one by one, wiped them in 

 order to remove the mother liquid adhering to 

 them, then pointed out to Biot the opposition 

 of their hemihedric character and separated 

 them into two groups: right crystals and left 

 crystals. 



"'You claim/ said Biot, 'that the crystals 

 placed on your right will deflect the plane of 

 polarisation to the right and that the crystals 

 placed on your left will deflect it to the left?' 



" 'Yes/ replied Pasteur. 



" 'Very well, I will attend to the rest/ 



"Biot prepared the solutions, and once again 

 sent for Pasteur. Biot began by placing in the 

 apparatus the solution which was supposed to 

 deflect to the left. When the deflection was 

 verified he took Pasteur by the arm and uttered 

 the phrase which has so often been cited and 

 which deserves to become famous: 'My dear 

 boy, I have loved science so dearly all my life 

 that this sets my heart beating!' 



" 'As a matter of fact/ Pasteur afterwards 

 said, in recalling this interview, 'it was evident 



