HEAT EQUIVALENT OF NUTRIENTS OF FOOD. G05 



tion. Tlie atoms in the iiioloeules of sucli snhstnnces would tlins in 

 turn assume new jiositions, and new compounds would be formed.^ 



In general G. von J^iigeli's^ explanation agrees witli this. He defines 

 fermentation produced by an organism as a transmission of tlie motion 

 of molecules, atom groujis, and atoms of the different compounds 

 making up the living plasma to other compounds which can receive it, 

 i. e., which can undergo fermentation. The compounds which impart 

 the energy remain unchanged. In iliose which receive it the equilibrium 

 is destroyed and the compound is broken u]). 



The two explanations have this in common. A wave motion pro- 

 ceeds from the substance which produces the fermeiitation. This is 

 communicated to the atoms of the substance to be fermented, sets 

 them in motion, and finally they assume a new condition of equilibrium. 



All the phenomena which are produced by the organized ferments 

 are produced by the unorganized ferments also. The real cause must 

 therefore in each case be the same. When the iuvertin produced by 

 yeast breaks cane sugar up into glucose and fructose, when the jiepsin 

 of the glands of the stomach changes albumen into peptone, when the 

 pancreatic juice changes starch to sugar and fats into glycerin and 

 fatty acids, we see in each case the same sort of change, and in each 

 case the causes must be the same. 



Since analogous results are produced at one time by organized fer- 

 ments and at another by unorganized ferments, one is forced to the 

 conclusion that the ferment organhins do not produce the fermentation 

 because tliey are or(iamsms but only because they are the carriers of 

 the real ferments. Alcoholic fermentation is no more produced by the 

 yeast plant than albumen is digested by the cells of the peptic glands. 

 Alcoholic fermentation is i^roduced by a ferment p)eculiar to the living 

 cell. It can not be separated from the cell, and when the cell dies it is 

 also destroyed. 



If we trace the cause of the widely varied forms of fermentation to 

 molecular vibrations which are induced by the ferments the same must 

 be true also for all kiiuls of catalytic reactions. 



A fragment of fibrin in a solution of peroxid of hydrogen produces a 

 violent evolution of oxygen, and water is formed. The motion which 

 proceeds from the fibrin disturbs the equilibrium of the extremely 

 unstable atoms in the peroxid of hydro.oen, and causes a new arrange- 

 ment of them. If other compounds which are also unstable, such as 

 silver oxid, gold oxid, or lead peroxid, come in contact with hydrogen 

 peroxid the motion of its atoms is so great that it reacts upon the 

 atoms of the compound which produced it in the first place and decom- 

 poses that also. 



One bubble of nitrous acid is sufficient to change an unmeasured 

 quantity of oleic acid to elaidinic acid, siucethis produces the vibration 

 in the atoms of the oleic acid necessary to effect the change. 



lAnn. Cliem., 153, p. 1. 



*Theorie der Giibning, Mnuicb, 1879, p. 29. 



