72 GTCAHAM LURK 



necessary, but there is a breaking up into various constituents which, 

 under certain circumstances, may remain Unoxidized. 



"Through the peculiarities of cellular structure the conditions of oxi- 

 dation are entirely different from those obtaining outside the cells. Under 

 ordinary circumstances nitrogen content means difficulty of decomposi- 

 tion, but in the body, protein is most readily destroyed. Hydrogen is 

 the most inflammable of the gases, but it can be resphed up to quantities 

 of hundreds of liters daily without being oxidized. 



"What the eye of the layman regards as rest is in reality an inter- 

 minable movement to and fro of the finest cellular particles, the most 

 complicated of all processes." 



Voit's theory of "organized protein'' and "circulating protein" served 

 its purpose in emphasizing the difference between the behavior of the 

 living protein of the tissue and the more readily metabolized protein of 

 the ingested food, even though the idea so troubled Liebig that, for the 

 thought of it, he could not tell his right hand from his left, and even 

 though it is now known that protein ingestion does not materially add 

 to the mass of blood protein. 



Voit, in his necrology of Pettenkofer (J), thus describes a few of the 

 results obtained by their combined efforts with the celebrated respiration 

 apparatus: "Imagine our sensations as the picture of the remarkable 

 processes of the metabolism unrolled before our eyes, and a mass of new 

 facts became known to us! We found that in starvation protein and fat 

 alone were burned, that during work more fat was burned, and that less 

 fat was consumed during rest, especially during sleep; that the car- 

 nivorous dog could maintain himself on an exclusive protein diet, and if 

 to such a protein diet fat were added, the fat was almost entirely de- 

 posited in the body; that carbohydrates, on the contrary, were burned, 

 no matter how much was given, and that they, like the fat of the food, 

 protected the body from fat loss, although more carbohydrates than 

 fat had to be given to effect this purpose; that the metabolism in the 

 body was not proportional to the combustibility of the substances outside 

 the body, but that protein, which burns with difficulty outside, metabolizes 

 with the greatest ease, then carbohydrates, while fat, which readily burns 

 outside, is the most difficultly combustible in the organism. 5 ' 



In Voit's great textbook, "Der Ifanclbuch der Erniihrung und des 

 Stoffwechsels" (18*1), one may read the words: "The methods deter- 

 mining the ingo and outgo of metabolic materials for animals and man 

 have very largely been devised by me." It was only Bidder and Schmidt, 

 with a crude respiration device, who had in any way approached the 

 methods of Voit. 



It has already been shown how the scientific susceptibilities of nations 

 may be aroused and how two men of different nations may have their 

 disagreements. The polemics which Pfliiger, in Bonn, wrote against Voit, 



