-BEUNI. 779 



Academy of Sciences of Stockholm and published in the proceedings 

 of that academy the following year (1886). In these memoirs there 

 is a ratiier notable limitation, namely, that all the aqueous solutions 

 of salts, acids, and strong bases are exceptions, in the sense that they 

 give too strong osmotic pressures. So van't Holf was obliged to intro- 

 duce into the equations which deal with them a coefficient i greater 

 than (figure) 1. This apparent exception was soon explained by a 

 young Swedish physicist, Svante Arrhenius, who, three years before, 

 had studied with great success the electric conductivity of solu- 

 tions; since the anomaly of which we first spoke is manifested in 

 solutions which possess electrolytic conductivity and since coeteris 

 paribus it is the more pronounced the greater this conductivity, he 

 supposes that the electrolytes are, at the moment of solution, largely 

 separated into their ions. 



It is thus that there originated the theory of electrolytic dissocia- 

 tion, which was inseparably connected from the first with that of 

 solutions, the struggles and triumphs of which it shared. 



Ojoposition could not be slow in developing. In fact the storm 

 of astonished indignation which soon after broke out in almost the 

 entire chemical world, was directed less against the theory of van't 

 Hoff than against that of Arrhenius, which seemed to be attempting 

 to overturn the most deep-rooted ideas; but objections to the first 

 were not lacking, especially in England. Wliile the greater number 

 of French scientists shut themselves up in an opposition based on 

 almost disdainful indifference, a group of chemists and of English 

 physicists, with Pickering, Armstrong, and Fitzgerald at their head, 

 partisans of the theory of hydrates, opened a real campaign against 

 the new ideas. Better inspired, however, they did not seek to avoid 

 discussion, but brought about a veritable war of words. 



Few public discussions will remain as memorable and as interesting 

 in the history of science as that which took place in 1890 at the meet- 

 ings of the British Association at Leeds when the three greatest rep- 

 resentatives of the new movement, van't Hoff, Arrhenius, and Ost- 

 wald, took part by express invitation. 



These are the terms in which Ostwald speaks of this tournament : 



I do not think I am wronging our hosts in supposing that the invitation had 

 been given first of all with the friendly intention of persuading us that we were 

 in error and of sending us back home again after a good lesson. And during 

 the first days our adversaries alone held the floor, so that one might have 

 thought up to a certain point that we were already scientifically dead. But 

 when, after long and lively personal discussions, the representatives of the 

 modern ideas finally had a chance to speak, even at the public sessions, the ap- 

 pearance of things was not slow in changing, and we were able to separate 

 from our hosts in amiable fashion and not without triumph. 



The ideas of our champions met a more cordial reception from Sir 

 Oliver Lodge ; and in the English field itself they found an influen- 



