IQI2] Frank R. Eider and William J. Gies 54 1 



competent to inhibit completely the Inauguration of edema by 

 hydrolases. 



We have made a preliminary inquiry into this matter by deter- 

 mining the influenae of pepsin and trypsin on the Imbibition of 

 water by coUagen and fibrin particles in suitable Solutions containing 

 sodium Chlorid. Our study has been similar in method to the work 

 described by Tracy and Gies. 



Accurately weighed portions of dry protein were quantitatively 

 transferred to tall, narrow, glass-stoppered, calibrated bottles, con- 

 taining Solutions of appropriate concentrations and exactly equal 

 volumes. Enzyme Solutions of precise preparation were then added 

 in sharply measured amounts to the respective mixtures. Suitable 

 control mixtures were made for each experiment. After their prep- 

 aration, each mixture was gently shaken several times at intervals 

 of about an hour. This treatment was always made mechanically 

 uniform for each series of tests. Sedimentation was practically 

 complete in an hour. The readings of bulk in c.c. on the calibrated 

 Scale were accurate within i c.c. 



At the end of the period of Observation, the liquids were sepa- 

 rated from the protein masses. In the experiments with collagen, 

 where digestive Solution was slight, this was done by ordinary filtra- 

 tion, which was continued over night (12-24 hr.) for the complete 

 removal of the free fluid. In most of the experiments with fibrin, 

 digestive Solution gradually became conspicuous; the liquids were 

 accordingly strained quickly through pieces of muslin of identical 

 size and the residual fluids completely expressed at once. 



Each experiment was begun early in the afternoon and the ob- 

 servations were continued for from 22 to 46 hours, or longer. 

 Environmental conditions were the same for each member of a 

 series of tests at every stage of an experiment. 



The data in Table i and 2 are typical of a group of about twenty 

 experiments. The prevailing concentrations of hydrochloric acid 

 and sodium carbonate, although not so favorable to our inquiry as 

 certain others would have been, were arbitrarily selected to repre- 

 sent influences more nearly comparable with biological conditions 

 than greater strengths would have afforded. The indicated con- 

 centrations of enzymes and salt were chosen, after preliminary tests, 

 in Order to develop maximal results under the conditions of cumula- 



