ENERGY TRANSFORMATIONS IN LIVING MATTER 127 



constructed membranes, behaving somewhat differently indeed 

 from those as yet fabricated by the art of man, but nevertheless 

 membranes, all the complex changes and transformations affected 

 by the cell are capable of explanation. 



The evidence of experiment clearly shows, however, that the 

 living cell is not a peculiarly constructed membrane obeying, even 

 where it most directly seems to disobey, the physical laws of 

 diffusion and osmosis; but is an energy machine or transformer by 

 virtue of the operation of which a form of energy appears peculiar 

 in its manifestations and phenomena to living matter, and pro- 

 ducing adaptations and combinations in non- vital matter, which in 

 many instances have not been imitated, and in others have only 

 been imitated by obviously different processes, by the application 

 of other forms of energy acting through non- vital transformers. 



At the same time it may be pointed out that this in no way 

 stultifies the application of physical chemistry to biological problems, 

 or minimises the great service which an increased knowledge of 

 physical chemistry has done and will do for biology. 



In recent times, advances in physical chemistry, and in the 

 knowledge of the properties of solutions, and of reactions occurring 

 in solution, have pointed the path to advances in biological science, 

 and it is in this direction that in the future most onward move- 

 ment is to be expected. 



A knowledge of physical chemistry, and more especially of the 

 laws and phenomena of solutions, both of colloids and crystalloids, 

 is indispensable to the modern biologist, taking that word in its 

 widest sense, for it is here that we shall gain our closest approach, 

 as far as can be at present seen, to the phenomena taking place in 

 the living cell. 



This follows because the cell in structure consists of colloids 

 and crystalloids in common solution in water, and hence much 

 may be gained by a knowledge of the laws of such a solution. 



It is imperative to add, however, that this peculiar solution 

 possesses something superadded, that this colloidal solution has a 

 structure and organisation which differentiate it from all non- 

 living colloids, such as starch, gelatine, or proteid in solution; 

 impress upon it peculiar properties ; and make it the scene of those 

 typical energy transformations which we aggregate together under 

 jbhe term life. 



It is unfortunate that the rebound from the bondage of the 



