THE ENERGY OF THE LIVING PROTOPLASM. l8l 



of the " units of life," whereby respiration would be induced."' 

 The dissociation he assumed to be followed by regeneration. 

 This barbarous idea of dissociation, however, would be incom- 

 patible with the great sensitiveness of the living protoplasm ; dis- 

 sociation would mean simply death and nothing else. 



But how can the living protoplasm, in spite of its extraordi- 

 nary sensibility, carry on such a powerful combustion process, 

 surpassing in energy the action of nitric acid, without being 

 injured ? Can we hold it possible that the oxygen is first 

 activified before it oxidises? It would seem to us that an 

 activified oxygen would have certainly other ways of action than 

 those observed within the living protoplasm. Respiration 

 exhibits like the well studied oxidations by various agents, (2) its 

 own specific manner of oxidising. An animal capable of oxidis- 

 ing in 24 hours several hundred grams of starch (sugar) completely 

 to carbon dioxide and water, (3) is unable to burn up a few grams 

 of oxalic or formic acid. (4) It is even unable to oxidise 1 gram 

 of benzene completely to phenol. And while it destroys tyrosin, 

 quinaldin, and pyrrol, it attacks with difficulty hydroquinon, 

 phenylacetic acid, or naphthoic acid. 



A series of investigations by Ncncki, Moving, Baumann, 

 Salkoivski, and others, led to the recognition that certain com- 

 pounds reappear in the urine unchanged, such as benzidine, 

 others in combination with sulphuric acid, as phenol, others 

 again (partially oxidised or not) as derivatives of glycocoll, like 

 picoline or benzoic acid, or of glucuronic acid, as tertiary alcohols 

 and thymol, or of cystin, as brombenzene; they may also re- 

 appear as uramido-compounds like sulphanilic acid, or taurin. 



(1) Physiologie des Keimungsprocesses, Jena, 1880; Jahresb. Thierchem., 22. 



(2) Potassium permanganate, nitric acid, hypochlorites, hydrogen peroxide, lead 

 peroxide, silver oxide, have all a specific oxidising action. The results may however 

 sometimes be modified by relatively small changes in the molecules to be oxidised, 

 as by the introduction of an acidic or alkylic radical. 



(3) The question as to the intermediary products is of relatively small im- 

 portance. The formation of glucuronic acid in animals shows that to a very small extent 

 acids are produced, but formic and oxalic acid certainly only in slight degree. The 

 forerunner of carbon dioxide is probably the bivalent group HC-OH, but that cannot 

 be proved. 



(4) Oxalate of sodium in non-lethal doses reappears in the urine with a loss of 

 only 7 per cent (Gaglio). Sodium formate reappears to the extent of in the 

 urine (Grchaut and Quinquaiid). 



