3/JO Chittenden and Smith — Diastatic Action of Saliva. 



Series Y. 



The saliva used in this series contained 0'091 per cent, alkali, cal- 

 culated as sodium carbonate : 



20 c.c. of the saliva were diluted to 100 c.c. and used in a. 



20 c.c. of the same saliva were neutralized and then diluted to 100 

 c.c. and used in b. 



a. normally alkaline saliva. 



Wt. Cu in Total amount Starch converted 



one-eighth. of sugar. Into sugar. 



4 C.C. saliva, 0-0652 gram. 0-2672 gram. 24-05 per cent. 



2 0-0282 0-1208 10-87 



1 0-0094 0-0464 4.17 



h. neutralized saliva. 



4 c.c. saliva, 0*0867 gram. 0-3536 gram. 31-83 per cent. 



2 0-0730 0-2984 26-72 

 1 0-0373 0-1560 14-04 



The ditterence in diastatic action in this instance, particularly 

 where the dilution is as 1 : 50 and TOO, is very great, yet in the case 

 of the greatest dilution of the unneutralized saliva the alkalinity of 

 the digestive mixture is but 0-00091 per cent, calculated as alkaline 

 carbonate. Moreover, there is a greater proportional diminution of 

 diastatic action in this case, and also -in the next greatest dilution 

 where the amount of alkalinity is 0-00182 per cent., than in the presence 

 of 0.00364 percent. ; a fact due either to the greater susceptibility of 

 the ferment to alkaline cai'bonate in a dilute solution or else to some 

 modifying influence of the larger amount of albuminous matter 

 present, a point which we shall return to later. 



Carrying the dilution of the saliva still further we tind that the 

 difference between the diastatic action of the neutralized and unneu- 

 tralized fluid, shows itself to the limit of decisive diastatic action. 



Series VI. 

 This sample of saliva contained 0"116 per cent, of alkali calculated 

 as sodium carbonate. The percentages of starch converted into 

 sugar dtiring 30 minutes at 40° C. alone are given. 



Thus in a dilution of I : 2000 in the case of neutralized saliva, dias- 



