346 Chittenden and Smith — Diastatic Action of Saliva. 



c. with 1 per cent, starch and 10 minntes at 40^ C. 



Wt. Cn in Total amount Starch converted 



one-eightli. of sugar. Into sugar. 



4 c.c. saliva. 0-057H gram. 0-2352 gran). 21- 15 per cent. 



2 00213 0-0928 8-35 



1 0-0091 0-0456 4-11 



h. with 2 per cent, starch and 30 minutes at 40° 0. 

 4 c.c. saliva. 0-0769 gram. 0-3136 gram. 19-26 per cent. 



2 0-0250 0-1080 4-86 



1 0-0103 0-0504 2-27 



c. with 2 per cent, starch and 4 hours at 40" C. 

 4 c.c. saliva, 0-1530 gram. 0-6248 gram. 28-13 per cent. 



2 0-1058 0-4312 19-41 

 1 00681 0-2784 12-53 



From these results it is seen that only when the dilution of 

 normally alkaline saliva is as 1 : 50 or 100 does the diastatic action at 

 all correspond to the amount of ferment present. The same is to 

 be noticed in Griitzner's* experiments, where the principle employed 

 by Gruenhagen in the estimation of pepsin was used; the amount of 

 starch dissolved by the saliva being directly proportional to the 

 amount of ferment only when very small quantities of saliva were 

 employed and the time limited to 10 or 15 minutes. Increasing the 

 amount of starch beyond 1 per cent, tends to diminish somewhat the 

 amount of sugar formed in a given time, when the dilution of the 

 saliva is as 1 : 50 or 100, which fact agrees well with what we already 

 know concerning the influence on ferment action of the clogging of 

 digestive fluids in general by the products of digestion, or by the 

 substance to be digested; series III, a and h. Increasing the length 

 of time for the ferment to act, however, causes a corresponding in- 

 crease in the amount of sugar formed, as is well seen in series III, c. 

 It would not be at all impossible therefore by suitable dilutions to 

 use this method as a means of determining the relative amounts of 

 ptyalin present in different salivary or pancreatic secretions. The 

 following results, taken from those already given, in addition to 

 others, lends favor to this view. All the experiments were made in 



* Plliiger's Arehiv dur Pliysiolugie, -xii, p. 294. 



