THE FERMENT OF MADDER ON SUGAR. 1 23 



I shall venture, in conclusion, to offer a few remarks on the 

 general nature of the process of fermentation here described, 

 and its relation to other processes of the same kind previously 

 known. 



The highly interesting and peculiar class of bodies called 

 ferments, comprises substances which are all of a very complex 

 nature, and are at the same time not characterized by any 

 marked peculiarities in their appearance, form, or general 

 properties. It is chiefly by their action on other bodies, by 

 the different species of decomposition which they induce in 

 the latter, and by the nature of the products thereby formed, 

 that we are enabled to distinguish the ferments from one 

 another, and arrange them in different classes. Now the 

 effects or species of decomposition produced by ferments are 

 of two kinds : general and specific. The general effects are 

 those produced by all ferments, without distinction, or are 

 common to several classes of ferments. The specific effects 

 are those peculiar to each ferment alone. The general effects 

 are again of different kinds, some being produced during the 

 first stages of the fermentation, others when the process has 

 somewhat advanced, others when it approaches a conclusion — 

 these different effects corresponding to different stages of 

 decomposition in the ferment itself. I think I am correct in 

 saying, that there are only two well-known instances of 

 specific effects due to ferments. The one is the decomposition 

 of amygdaline (and salicine?) by means of emulsine, the 

 ferment contained in almonds; the other the decomposition 

 of rubian by means of erythrozym. No known ferment, 



vetches, and that the asparagine, by fermentatioD, yields succinic acid. 

 Dessaignes could not discover what body contained in the seeds it is, which 

 leads to the formation of asparagine, but he found that pea flour, when allowed 

 to ferment with caseine, produced considerable quantities of succinic acid. It 

 is now evident that this acid may have been formed directly from the starch of 

 the pea flour, though it is possible (and it would be a fact of uncommon interest 

 if it were discovered to be the case), that the latter pastes through the intflr- 

 mediate stage of asparagine. 



