WILLIAM D. HARKINS 



165 



essentially monomolecular at sufficient concentrations of the solutions. With long- 

 chain (10 carbon atoms) compounds, only dilute aqueous solutions are obtained, so 

 the time necessary for the diffusion of sufficient organic substance into the surface to 



Fig. 17. — Perspective drawing and photograph of filmometer (design of B. B. Freud, a modi- 

 fication of the filmometer of N. K. Adam). 



