DIGESTION. 201 



in starvation a thin fluid is secreted, and after partaking of 

 food a thick fluid is produced. According to the observations 

 of BERNSTEIN, HEIDENHAIN, and others, the secretion increases 

 rapidly after eating, and it reaches its maximum in the cours^pf 

 the first three hours. From this time the secretion diminishes, but 

 may again increase from the 5th-7th hour, when generally large 

 quantities of food pass from the stomach to the intestine. Then 

 it again decreases continuously from the 9th-llth hour, and stops 

 entirely at the 15th-16th hour. 



The statements as to the amount of pancreatic juice secreted 

 in the course of 24 hours are variable and not trustworthy. 

 It seems positively proved that the permanent fistula yields a con- 

 siderably larger quantity of secretion than the temporary. While 

 KEFERSTEIN and HALLWACHS, and SCHMIDT and KROGER, find that 

 the quantity of juice secreted from the first is 45-100 grms. per 

 kilo during 24 hours, BIDDER and SCHMIDT and BIDDER and 

 SKREBITZKY claim that the quantity from the temporary fistula is 

 2.5-5 grms. per kilo in the same time. 



In regard to the constituents and composition of the pancreatic 

 juice, a distinction must be made between the secretion of a tem- 

 porary and of a permanent fistula. The secretion flowing from the 

 former is in dogs a clear, colorless, n early-si rupy, odorless fluid of 

 an alkaline reaction which is very rich in albumin and sometimes 

 containing so large a quantity that it coagulates like white of egg 

 when heated. Besides albumin the juice contains also three- en- 

 zymes one diastatic, one fat-splitting, and one which dissolves 

 proteids. The last-mentioned has been called trypsin by KUHNE. 

 Besides the above-mentioned bodies the pancreatic juice habitually 

 contains small quantities of leucin, fat, and soaps. As mineral 

 constituents it contains chiefly alkali chlorides, also alkali carbo- 

 nates, and some phosphoric acid, lime, magnesia, and iron. 



The secretion from the permanent fistula always contains less 

 solids, especially albumin and enzymes, than that from a tempo- 

 rary fistula. A long time after the operation it is more fluid, more 

 strongly alkaline, and the property which the juice from the tem- 

 porary fistula has of dissolving albumin is often absent, or the 

 secretion shows it in only a slight degree. As an example of the 

 different composition of the juice from a temporary and from a 



