66 



COMPARATIVE HYDROLYSIS OF GELATIN 



CC.^ 



2 3 



Days at 22° 



Fig. 5. Hydrolysis of gelatin by trypsin alone. 8 cc. of 10 per cent trypsin 

 were added to 200 cc. of 5 per cent gelatin containing 10 cc. of 1.0 M Na2C03, 

 and the solution kept at 22°. 25 cc. samples pipetted out at intervals and kept 

 at 3°C. until all had been collected. 1 cc. of 10 per cent trypsin was then added 

 to each sample, the bottles placed at 22°, and formol titration was run on 5 cc, 

 as shown in the figure. The values plotted have been calculated on the basis of 

 10 cc. of 5 per cent gelatin. 



