360 



PROTOPLASM 



Fia. 156. — A. A U tube for demonstrating cataphoretic flow; the solution in 

 the right arm of the U is opaque due to concentration of AS2S3 at that (the 

 jiositive) pole. B. The Pauli cataphoresis chamber for proteins. C. The 

 Northrop-Kunitz cataphoresis chamber mounted on a microscope. 



