SOAPS, PROTEIN DERIVATIVES AND TISSUES 243 



4. Concluding Remarks 



In these concluding paragraphs we shall in rather dogmatic 

 fashion try to group the results of the studies outlined in these 

 pages with some older ones, 1 all of which had in common the pur- 

 pose of analyzing protoplasm colloid-chemically and of defining 

 as accurately as possible the nature of various changes observable 

 in the living mass when subjected to physiological or pathological 

 change. 



1 



Biological evidence indicates that of the five proximate prin- 

 ciples found in protoplasm, protein, carbohydrate, fat, salt and 

 water three constitute an irreducible minimum. While life 

 may continue in 'the absence of carbohydrate and fat it ceases 

 as soon as any of the other three is missing. What is the relation- 

 ship of these to each other? In the common belief these materials 

 exist " in dilute solution " in the cells which, plainly put, are held 

 to be little bags of salt solution in which the proteins are either 

 dissolved or " suspended." And yet, normal protoplasm even 

 when very rich in salts has not a salty taste and does not yield 

 any appreciable portion of its salt content to rain or dew 2 or 

 the distilled water in which it may be bathed. The salts are 

 obviously not in dilute solution but combined with the protein. 

 Biological reasoning therefore compels the same conclusion 

 to which the analogies existent between the behavior of simple 

 (protein) colloid systems and the behavior of living matter have 

 led us. The so-called " salts " and the water of protoplasm (except 

 in theoretical amounts) are not "free" The salts are combined with 

 the proteins and the combination is not " dissolved " in water, but 

 conversely, water is dissolved in it. Living matter is in essence a 

 unit, a hydrated basic-protein-acid complex in which ionization, 

 the laws of true solution and the presence of water in a state 

 analogous to that seen in a glass are reduced practically to zero. 3 



1, 19 (1917); ibid., 28, 50, 517 (1918); Proc. Son. Exp. Biol. and Med., 14, 

 140 (1917); H. B. WEISS: Jour. Am. Med. Assn., 68, 1618 (1917); ibid., 71, 

 1045 (1918). 



M M: 1 1 II FISCHER and MARIAN O. HOOKER: Fate and Fatty Degen- 

 niti.m \.u Y..rk 1917); MM; ri\ II FISCHER: (Edema and Nephritis, 

 3rd K.I. \.-w ftffi I '.-' I 



'See JOHN IK. LUJYD: Eclectic Med. Jour., 76, 610 (1915). 



1 What is said here of the "salts" which obviously are made when pro- 



