176 LABORATORV GUIDE IN PHYSIOLOGY. 



Sol. B. The resulting mixture is a standard artificial 

 gastric juice of the formula given above, and has the 

 power of completely digesting at 38-40C one-fifth its 

 weight of coagulated egg albumin in six hours.* 



From a standard gastric juice prepare the following 

 dilutions using 0.1% HC1 as a diluent. It is scarcely 

 necessary to say that the greatest care should be 

 taken, (1) to make all measurements with preci- 

 sion; and (2) to thoroughly shake each dilution before 

 drawing off the material for the next lower dilution. 

 (#) Standard artificial gastric juice 10 c. c. + 1 c. c. 



moist fibrin. 

 () ^ standard artificial gastric juice 10 c. c.-(-l c. c. 



moist fibrin. 

 (0 liu standard artificial gastric juice 10 c. c.-(-l 



c. c. moist fibrin. 



(d) T o j o7 standard artificial gastric juice 10 c. c.-f-l 

 c. c. moist fibrin. 



(e) -fo,Vi>T) standard artificial gastric juice 10 c. c.-f-l 

 c. c. moist fibrin. 



(/) T^O!OOO standard artificial gastric juice 10 c. c.-j- 



1 c. c. moist fibrin. 

 C?0 T.inFo.innF standard artificial gastric juice 10 c. c.-f- 



1 c. c. moist fibrin. 



Keep tubes in incubator or water bath at 38-40C. 

 Note (1) time required to dissolve fibrin completely, 

 (2) time required to change all acid albumin to pro- 

 teose or peptone. Will one millionth standard gastric 

 juice digest fibrin at all? Will a lower dilution (one 

 ten-millionth) digest it; if so, how dilute, and how 

 long a time is required? 



*For details of testing standard gastric juice see Pharmacopoeia. 



