Ii6 



Scientific Proceedings (119). 



table 1. 



Collodion Membranes. 

 Percentage of Sodium Chloride Diffusion in Twenty Minutes. 



Drying Time, (Minutes and Seconds). 



1:30 



i:4S 



2:00 



4:00 





30% 



30% 



30% 



29% 





31% 



30% 



30% 



30% 



3 



30% 



29% 



28% 



28% 



TABLE II. 

 "Lecithin "-Collodion Membranes. 

 Percentage of Sodium Chloride Diffusion in Twenty Minutes. 



Drying Time, (Minutes 

 and Seconds). 



1:30 



i:4S 



2:00 



2:15 



2:30 



3:00 



4:00 





<2% 



1% 



25% 



21% 



30% 



27% 



28% 





1% 



6% 



27% 



11% 



29% 



30% 



28% 



3 7 : 



<I% 



<i% 



24% 



27% 



28% 



28% 



29% 



4 



3% 



12% 



3% 



28% 



28% 



28% 



29% 



5 





8% 







28% 



28% 



26% 



collodion membranes were all clear and had a practically constant 

 diffusion rate. This is suggestive of the possibility that the change 

 in the size of the aggregates of lecithin molecules may have here 

 influenced the rate of passage of the salt. Neither structure nor 

 fat-droplets were visible under the oil-immersion of stained and 

 unstained sections. In this connection it is interesting to note 

 that membranes prepared with olive oil become definitely cloudy 

 in less than one minute before fixation and this cloudiness persists 

 after fixation. In these membranes definite oil droplets are visible 

 under low power. Curiously enough both olive oil and lecithin- 

 collodion membranes are clear after fixation when the drying time 

 was extended over hours. The study of these membranes is 

 incomplete. 



Conclusions. 



I. Changes in the drying time, to four minutes, of membranes 

 prepared from collodion and fixed with water does not appreciably 



