426 PROCEEDINGS OF THE AMERICAN ACADEMY. 



by the fact that the later experimenters investigated parts only of the 

 wide field outlined in 1892, the relation of the parts to the whole 

 being partially unperceived. The paper also shows that the unequal 

 escape of oxygen and nitrogen imprisoned in the oxides of metals is a 

 phenomenon of great interest, capable of shedding light on the internal 

 kinetics of solids. 



Cambkidge, May 1, 1898. 



