72 Studies of Diffusion through Rubber Membranes [Sept. 



TABLE I (continued) 

 Third Series. With Rubber Condoms. 



FouRTH Series. With Bags of Sheet Rubber.* 



B. Data showing that the diffusible biuret-reacting material ii-15) 



was true protein 



Fifth Series. With Rubber Condoms. 



SixTH Series. With Bags of Sheet Rubber.* 



Seventh Series. With Rubber Condoms. 



20 



31 



3 

 3 



40 c.c. ether-alc. sol. 

 40 c.c. ether-alc. sol. 



Abs. ether 

 Abs. ether 



+ 

 + 



+ 

 + 



+ 

 + 



No leak 

 No leak 



•This control experiment (10) was carried out in duplicate, with negative 

 results in each case. 



*In this experiment (11) a new, clean, empty condom, with the bottom 

 removed, was suspended in absolute ether, for " control " purposes. 



* " Pure Mexican plantation rubber." 



