6 PHYSIOLOGICAL CHEMISTRY. 



just described. In combustion in the ordinary sense, as, for 

 example, the burning of wood or oil, we must not forget that 

 the substances themselves do not combine with oxygen. It is 

 only after the action of heat has decomposed these bodies to a 

 certain degree that the oxidation of the products of such decom- 

 position takes place and is accompanied by the phenomenon of 

 light. 



The numerous intermediary products of decomposition which 

 we observe in the animal body teach us that the oxidations and 

 splittings of the components of the body do not take place at once 

 and suddenly, but only very gradually, step by step, until the final 

 products of exchange are reached. 



A very instructive example, of such a gradual decomposition 

 outside of the organism has been shown by DKECHSEL in his in- 

 vestigation on the electrolysis of phenol by an alternating current. 

 By experiments with alternating electric currents we obtain, of 

 course, in the watery solution of the substance, at each electrode 

 alternately, oxygen and hydrogen in great rapidity. Therefore 

 oxidations and reductions must take place alternately, and we ob- 

 tain syntheses as well as splittings with oxidations. 



If phenol in watery solution is treated with such an alternating 

 current, we produce, by the combined action of reduction and 

 oxidation processes, where all double linking in the benzol ring is 

 broken by the aggregation of hydrogen atoms with simultaneous 

 solution, and followed by an oxidation with the elimination of 

 hydrogen atoms, a new body, hydro-phenoketon, C e H 10 0, or 

 OH, 



TT P/ \Pf) 



I 0' 'OH * From *ke hydro-phenoketon a compound of the 



1 X 



fatty series is produced by the fixation of -f- 2H accompanied 

 with the splitting of the benzol ring, namely, normal caproic acid, 



OH, 



O.H.A, or H,C| JcH H - B y further electrolysis of the ca- 



' CH, 

 proic acid, with the removal of carbon as carbon dioxide and of 



