THE LIFE OF PASTEUR 



fixed his mind on his present object, which was the application 

 of science to the brewing industry. 



" The interest of those visits to English breweries," wrote 

 Pasteur to Kaulin, " and of the information I am able to col- 

 lect (I hear that I ought to consider this as a great favour) 

 causes me to regret very much that you should be in want of 

 rest, for I am sure you would have been charmed to acquire 

 so much instruction de visu. Why should you not come for 

 a day or two if your health permits? Do as you like about 

 that, but in any case prepare for immediate work on my 

 return. We need not wait for the new laboratory ; we can 

 settle down in the old one and in a Paris brewery." 



When Pasteur returned to Paris, Bertin, who had not seen 

 him since the recent historic events, welcomed him with a 

 radiant delight. School friendships are like those favourite 

 books which always open at the page we prefer ; time has no 1 

 hold on certain affections ; ever new , ever young , they never 

 show signs of age. Bertin 's love was very precious to Pasteur, 

 though the two friends were as different from each other as 

 possible. Pasteur, ever preoccupied, seemed to justify the 

 Englishman who said that genius consists in an infinite 

 capacity for taking pains; whilst Bertin, with his merry eyes, 

 was the very image of a smiling philosopher. In spite of his 

 position as sub-director, which he most conscientiously filled, 

 he was not afraid to whistle or to sing popular songs as he 

 went along the passages of the Ecole Normale. He came 

 round to Pasteur's rooms almost every evening, bringing with 

 him joy, lightness of heart, and a rest and relaxation for the 

 mind, brightening up his friend by his amusing way of look- 

 ing at things in general, and at that time beer in particular. 



Whilst Pasteur saw but pure yeast, and thought but of spores 

 of disease, ferments, and parasitic invasions, Bertin would 

 dilate on certain cafes in the Latin quarter, where, without 

 regard to great scientific principles, experts could be asked 

 to pronounce between the beer on the premises and laboratory 

 beer, harmless and almost agreeable, but lacking in the refine- 

 ment of taste of which Bertin, who had spent many years in 

 Strasburg, was a competent judge. Pasteur, accustomed to 

 an absolutely infallible method, like that which he had in- 

 vented for the seeding of silkworms, heard Bertin say to him, 

 " First of all, give me a good bock, you can talk learnedly 

 afterwards." Pasteur acknowledged, however, the improve- 



