VALIDITY OF THE PRINCIPLE OF LE CHATELIER. 37 



changes of any kind in the parameters A or P, with this restriction, 

 it is true, that we have, following Le Chatelier, interested ourselves 

 solely in the ultimate effect upon equilibrium, leaving entirely out of 

 consideration the path by which such equilibrium is reached. In 

 many cases such partial information is of value, the equilibrium being 

 the matter of chief interest, the path of the change of lesser practical 

 importance. Herein lies the utility of such general principles as that 

 of Le Chatelier, of Maupertuis, Lenz and others whose names have 

 become linked with one or other form of reciprocal relations between 

 the parameters defining a state of equilibrium. Since the application 

 of such principles to biological systems has been essayed by various 

 authors, without, however, any rigorous foundation upon which to 

 build, it has appeared to the writer essential, for further progress in 

 this field, to make a critical examination of the basis underlying these 

 principles. 



