170 MODERN SCIENCE READER 



declaring novel facts and fancies, and a veritable whirlpool 

 of conflicting statement and contending argument ensued. 

 At this distance of time the multitude grows dim ; but cer- 

 tain figures stand out, and are conspicuous among their 

 clamorous fellows. We must note at least four remarkable 

 personages by name, Schwann, de Latour, Berzelius, and 

 Liebig. The labors of de Latour in France and Schwann 

 in Germany were almost simultaneously crowned with 

 eventful discovery. Yeast, they announced with no un- 

 certain voice, is a living, breeding entity, and, moreover, 

 is the cause of the fermentation of sugar. All this hap- 

 pened during the opening year of the Victorian age, and 

 against these strange utterances many a voice was raised. 

 Those of us who have studied the history and progress in 

 the fermentive arts will easily recall some of the wild and 

 fantastic guesses which were then poured forth ; but among 

 much intellectual dross there rang out the reasoned opinions 

 of Berzelius, the Swede, and Liebig, the giant of his time. 

 Berzelius had, without doubt, as early as 1827, and with 

 greater certainty in 1839, regarded fermentation as de- 

 pendent upon catalytic force, or, as he called it, vis occulta, 

 and Liebig, whose chemico-mechanical theory held ground 

 for some years, is best interpreted by quoting his own 

 words, as they appear in the classic Chemistry of Agri- 

 culture and Physiology. "In the metamorphosis of 

 sugar," says he, "the elements of the yeast, by contact with 

 which its fermentation was effected, take no appreciable 

 part in the transformation of the elements of the sugar; 

 for in the products resulting from the action we find no 

 component part of this substance." 



Many other theories echo from out those times theories, 

 for the most part, utterly vanished from the ken of prac- 

 tical science. Albeit a strange value, a vague sense of 

 prophecy is discernible in certain of these long-forgotten 

 figments of scientific imagination. For instance, one might 

 legitimately recall Mitscherlich, with his notion of contact, 

 much akin to the action of platinum sponge, or Meissner, 



