46 PROTEOLYTIC PANCREATIC FERMENT 



the pancreas adapts itself to its work in, as it were, an 

 intelligent manner, by increasing its proteolytic ferment for 

 meat, its amylolytic ferment for a meal of bread, or its 

 lactose ferment for milk. This view, however, cannot with- 

 stand criticism ; it bespeaks an effort to realize a harmonious 

 principle pervading the arrangements of nature which goes 

 somewhat too far afield. 27 



Quantitative Determination and Ferment Law of Tryp- 

 sin. The realization that there are a number of physiological 

 questions related with trypsin which rest upon the possibility 

 of its quantitative determination, has, as in case of pepsin 

 and by employment of similar principles, led to numerous 

 attempts to accomplish this. Thus Metts ' tubes of albumin 

 or gelatin have been used. 28 Trypsin has been allowed to act 

 upon dissolved casein, after Vollhard's method, 29 and from 

 the increase of acidity of the resulting albumoses the degree 

 of digestion has been determined by titration. Gross 30 dis- 

 solves casein in soda solutions (as in E. Fuld's method), 

 arranges a series of tubes with increasing amounts of 

 trypsin, and observes after a time whether acidulation with 

 acetic acid continues to give rise to turbidity. Jacoby 31 ob- 

 serves the degree of clearing of deposits of ricin or edestin ; 

 V. Henri 32 and Bayliss 33 follow the progress of digestion 

 physico-chemically by determining the conductivity, and 

 Brailsford Robertson 34 by determining the refraction index 

 of a soda-casein-solution after precipitation of undigested 

 casein by acetic acid. A simple and apparently very precise 



27 Literature upon Adaptation of Pancreatic Secretion to Food : S. Rosen- 

 berg, Handb. d. Biochem., 3', 138-140, 1910. 



a P. Hattori, Arch, internat. de Pharm., 18, 255, 1909. 



28 W. Lohlein, Hofmeister's Beitr., 7, 120, 1905 ; Faubel, ibid., 10, 35, 1907. 

 80 0. Gross, Arch. f. exper. Pathol., 58, 157, 1908. 



111 M. Jacoby, Biochem. Zeitschr., 10, 299, 1908. 



82 V. Henri, and Larguier des Bancels, C. R. S'oc. de Biol., 55, 563, 787, 866; 

 Jahresber. f. Tierchem., S3, 512-514, 1903. 

 88 W. M. Bayliss, 1. c. 

 14 T. Brailsford Robertson, Journ. of Biol. Chem., 12, 23, 1912. 



