710 FRANCIS H. McCRtJDDEN 



organism are the chief determining factors in the processes of combustion 

 within the organism, has been confirmed" (von Noorden(/i)). 



These three books are cited, because, being probably the most widely 

 read, popular books dealing with metabolism, physicians are presumably 

 familiar with them. Yet misconception on this fundamental point is most 

 widespread, and in the belief that the extent of oxidation is determined by 

 the oxygen supply, many pathological conditions are attributed to im- 

 perfect or defective oxidation. 



In the older textbooks physiological oxidation is sometimes compared 

 with the blacksmith's fire, the lungs with the bellows ; the intensity of the 

 metabolism being attributed to the activity of the respiration. This com- 

 parison, though no longer appearing in these words, still appears in prin- 

 ciple ; it is the basis of the idea expressed in the hypothesis so frequently 

 seen in our medical journals, the "condition is due to products of insuffi- 

 cient oxygen supply." 



One of the best known examples of this hypothesis is the belief that 

 gout and the "uric acid diathesis" are due to the accumulation of products 

 of incomplete oxidation. According to this hypothesis, uric acid is the 

 immediate antecedent of urea in the oxidation of protein in the body; 

 urea is the normal end product, but when oxidation is deficient, part of the 

 protein may be oxidized only to uric acid (Haig). Liebig expresses a com- 

 mon belief when he says that sufferers from uric-acid concretions, who 

 go to the country, sometimes, as a result of the better oxygenation, de- 

 velop concretions of oxalic acid instead; and that when these same indi- 

 viduals, as a result of exercise, absorb still more oxygen, the concretions are 

 completely oxidized to carbon dioxid and water (Liebig). Animals that 

 drink much water, according to Liebig, excrete less uric acid than others ; 

 the water keeps the sparingly soluble uric acid in solution, so that it 

 becomes more completely oxidized to urea. 



Many investigators have attributed symptoms in leukemia, chlorosis, 

 and emphysema to the products of incomplete oxidation, believing that the 

 symptoms result from decreased external or internal respiration respec- 

 tively (Bartels, Jacubasch, Mosler and Korner, Sticker, Virchow(a) (&)). 

 It is stated that the fat found in the parenchyma of organs in an- 

 emia is deposited because the oxygen supply to the organs is insufficient to 

 burn the fat (Bauer, Frankel(a)). Another finding in anemia, an in- 

 crease in the proportion of urinary sulphur excreted in the form of unoxi- 

 dized, neutral sulphur, has been attributed to the imperfect supply of 

 oxygen to the tissues (Rudenko, Salkowski(6), Schmidt, Schupfer e de 

 Rossi (6)). Later investigations have not confirmed this finding (Stadt- 

 hagen(6), Taylor, von Moraczewski(cO). The introduction of hypo- 

 phosphites into medicine was due to the belief that phthisis is due to in- 

 complete oxidation (Editorial). Phosphoms and its partly oxidized deriva- 

 tives, the hypophosphites, were recommended in this disease in the belief 



