414 THE BEGINNINGS OF LIFE. 



by reason of its own instability, or on account of the 

 greater instability of some more mobile substance with 

 which it is brought into contact. He says: c Many 

 organic compounds are known which undergo., in 

 presence of water, alteration and metamorphosis having 

 a certain duration, and ultimately terminating in putre- 

 faction j while other organic substances that are not 

 liable to such alterations by themselves, nevertheless 

 suffer a similar displacement or separation of their 

 molecules when brought into contact with the former 1 / 



1 ' Pharm. Journal,' 1870. This statement is illustrated by Gerhardt 

 when he says ('Chimie Organique,' t. iv. p. 474): 'En presence de 

 1'eau, le gluten s'altere continuellement ; si on le delaye dans 1'eau et 

 qu'on 1'abandonne dans cet etat a la temperature ordinaire, il se gonfle 

 peu k pen en degageant beaucoup de gaz acide carbonique melange 

 d'hydrogene non carbone, et d'hydrogene sulfure ; en meme temps il se 

 ramollit et se fluidifie entierement ; 1'eau qui le recouvre devient alors 

 acide, et contient de la leucine, du phosphate et de 1'acetate d'ammoni- 

 aque ; finalement le gluten se fonce de plus en plus et se dissout presque 



entierement Pendant les differentes phases de sa transformation 



le gluten possede la propriete d'agir comme fermente a la maniere des 

 autres substances albuminoides. Avant de subir lui-meme la ferment- 

 ation putride, il possede la propriete' de faire subir une metamorphose 

 remarquable k la matiere amylacee. En effet lorsqu'on ajoute de la 

 farine de ble a de 1'empois d'amidon delaye dans 1'eau et qu'on expose 

 ce melange, pendant quelques heures, k une temperature de 60 a 70 C, 

 il perd sa consistence, se fluidifie, et finalt'ment devient entierement 

 sucre; la matiere amylacee se trouve alors convertie soit en dextrine, soit 

 en glucose.' It should be observed that the temperature at which this 

 change takes place, 60-70 C (i4O-i58F), precludes the possibility 

 of its being brought about by living organisms, since Bacteria and 

 TorulfE are uniformly killed by exposure for a few minutes to a tem- 

 perature of i40F. The recent researches of Hoppe-Seyler (' Med. 

 Chem. Unters,' 1871, pp. 557-581), also show that living ferments are 

 killed by temperatures which do not destroy the virtues of dead ferments. 



