EVOLUTION OF COLLOIDS 125 



Legions of cases exist in which two or more 

 molecules, themselves completely saturated 

 atomically, and incapable of attaching to 

 their molecule a single additional atom, 

 unite most strongly to one another with 

 evolution of energy, and this without the 

 loosening of any atomic affinities. 1 



The theory of atomic valencies entirely 

 fails to account for such combinations, 

 and so through lack of invention and scientific 

 imagination, they were simply cast upon one 

 side and ignored by the chemist as purely 

 physical phenomena, just as if that removed 

 them from the pale of research by throwing 

 them into the dust-heap of another scientist. 

 The physicist was content to classify them with 

 a confused heap of phenomena ascribed to 

 surface reactions, or condensations upon 

 surfaces, and having invented the term 

 adsorption to designate such phenomena, 

 the physicist, too, rested upon his laurels. 



Now, in many cases, the amount of energy 

 set free as heat, when a number of molecules, 

 each completely saturated atomically, unite 

 together is of far too high an order of magni- 



1 For details, the reader acquainted with chemistry 

 is referred to a paper entitled " The role played by mole- 

 cular affinities in bio-chemical reactions," Benjamin Moore, 

 Archivio di Fisiologia, vol. vii,, 1909, Anniversary 

 volume in honour of Guilio Fano. 



