110 PASTEUR 



manufacture could derive from the method of 

 the French scientist, and the microscope be- 

 came a frequently consulted instrument in their 

 breweries. 



Upon returning to Paris, and once more in- 

 stalled in his laboratory at the Ecole Normale, 

 Pasteur still continued his studies of beer. The 

 problem to be solved was a very delicate one. 

 As a matter of fact, a beer may be good, even 

 perfect, and yet be unpalatable, for the ques- 

 tion of taste intervenes, quite aside from the 

 quality of the manufacture. 



"Now, for the purpose of carrying on this 

 work of adaptation and of detail," writes M. 

 Duclaux, "Pasteur had none of the essential 

 requisites. He did not like beer, and, although 

 by force of will, he succeeded in acquiring a 

 sufficiently trained palate and sense of taste, he 

 remained unable to detect differences pointed 

 out by the brewers themselves, and which he 

 was sometimes amazed to find keenly appre- 

 ciated by his friend Bertin, who lived next to 

 him in the Ecole Normale (as assistant direc- 



