NEWEST IDEAS AS TO WHAT IS LIFE 



very recently it has become clear that the walls of 

 the intestines themselves secrete a substance whose 

 office is to complete the work of the stomach ; which 

 may explain why it is that dried pepsin from the 

 pig's stomach is not the dyspeptic's digest-it-all 

 that had been hoped. 



Like animals, the plants were found to contain 

 similar substances; and of the same sort are the 

 rennet which curdles milk, the active part of 

 brewer's malt, and some of the powerful vegetable 

 and animal poisons even. 



The common property of all of these peculiar 

 substances is their ability to digest or split up 

 quantities of the substances they attack, out of all 

 proportion to their own mass. A given amount 

 of the active principle of malt will, for example, 

 break up a million times its own weight of sugar. 



So close was the resemblance in their effects of 

 these near -related families of substances to the 

 ordinary fermentation of yeast-cells and the mi- 

 crobes that they came to be called the soluble 

 or formless ferments, as opposed to the organized 

 or living ferments, the bacteria and fungi. French 

 workers patriotically call them diastases, after the 

 parent discovery ; Germans prefer enzymes ; others, 

 zymases. 



It fell to Buchner's admirably conceived ex- 

 periment to disclose the identity in principle of all 



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