214 THE LIFE OF PASTEUR 



2. These germs of ferments are brought by the air, by the 

 ingredients, or by the apparatus used in breweries. 



3. Whenever beer contains no living germs it is unalterable. 

 When once those principles were formulated and proved 



they were to triumph over all professional uncertainties. And 

 in the same way that wines could be preserved from various 

 causes of alteration by heating, bottled beer could escape the 

 development of disease ferments by being brought to a tem- 

 perature of 50 to 55. The application of this process gave 

 rise to the new word " pasteurized " beer, a neologism which 

 soon became current in technical language. 



Pasteur foresaw the distant consequences of these studies, 

 and wrote in his book on beer 



( ' When we see beer and wine subjected to deep alterations 

 because they hare given refuge to micro-organisms invisibly 

 introduced and now swarming within them, it is impossible 

 not to be pursued by the thought that similar facts may, must, 

 take place in animals and in man. But if we are inclined to 

 believe that it is so because we think it likely and possible, 

 let us endeavour to remember, before we affirm it, that the 

 greatest disorder of the mind is to allow the will to direct 

 the belief." 



This shows us once more the strange duality of this inspired 

 man, who associated in his person the faith of an apostle with 

 the inquiring patience of a scientist. 



He was often disturbed by tiresome discussions from the 

 researches to which he would gladly have given his whole 

 time. The heterogenists had not surrendered ; they would 

 not admit that alterable organic liquids could be indefinitely 

 preserved from putrefaction and fermentation when in contact 

 with air freed from dusts. 



Pouchet, the most celebrated of them, who considered that 

 part of a scientist's duty consists in vulgarizing his discoveries, 

 was preparing for the New Year, 1872, a book called The 

 Universe: the Infinitely Great and the Infinitely Small. He 

 enthusiastically recalled the spectacle revealed at the end of 

 the seventeenth century by the microscope, which he com- 

 pared to a sixth sense. He praised the discoveries made in 

 1838 by Ehrenberg on the prodigious activity of infusories, 

 but he never mentioned Pasteur's name, leaving entirely on 

 one side the immense work accomplished by the infinitely 

 small and ever active agents of putrefaction and fermentation. 



