Electrolytic Crystallization of Metals. 31 



the mere act of solution. When we consider that the atoms of 

 tin and chlorine appear to have a considerable mutual attraction 

 this seems absurd, and if we take another metal with even a 

 greater affinity for chlorine the absurdity is still more evident. 

 One ounce of the metal aluminium, in combining with the 

 equivalent quantity of chlorine, evolves energy sufficient to 

 shoot a ton weight over 300 feet high in the air, that is, if all 

 the energy could be applied to shooting tons into the air. 



Are we to suppose, that when we dissolve the resulting 

 aluminium chloride in water, the whole 300 foot-tons are 

 temporarily annihilated and the atoms separate again to suit 

 the impatient exigencies of modern electrolytic assumptions ; 

 or are we as an alternative to assume that, though the joining 

 together of the atoms evolves this amount of energy, their 

 separation may be effected without its absorption ? Both 

 hypotheses seem to me most doubtful. 



Nevertheless this theory has in recent times been revised 

 by some of the German physicists under the name of the dis- 

 sociation theory. It has also been called the - Williamson- 

 Clausius hypothesis because it was stated to have been supported 

 by these authors. In a paper published in the Philosophical 

 Magazine three years ago, I showed that it was not supported 

 by Williamson, so that this name does not apply. I have 

 suggested another however, the neatness, comprehensiveness, 

 and appropriateness of which, considering the German origin 

 of the theory, will I doubt not be recognised. It is 



Freidochgebundendurchcontactelectrisirtetheilmoleculishebeweglichkeir. 



The theory would appear to be quite as long-winded, intricate 

 and impossible as the name. We shall, therefore, dismiss it 

 and turn to a much simpler hypothesis which is based on the 

 electrolytic theory of Grotthus and is the modification of this 

 accepted by Faraday. With that modesty which characterised 

 the unassuming greatness of his mind he refused to follow a 

 hypothesis, so unwarranted as that involving electrified atoms, 

 and gently putting it aside proceeded to free himself and his 

 writings from all danger of connexion with it by coining new 

 electrolytic nomenclature. I regret to add that many of Faraday's 



