499 TRANSACTIONS OF SECTION B. 
or two has been put in place, although scarcely ‘ well and truly laid ’—but 
the actual buildings are barely marked out. In point of fact, the needs to 
which I called attention in 1885 are our present and now most urgent needs. 
But of this more subsequently. 
In discussing chemical action, I commented on our failure to arrive at 
any understanding as to the conditions which determine the occurrence of 
chemical change—a failure all the more remarkable in view of the clearness 
of Faraday’s early teaching. Basing my remarks on the thesis which he pro- 
pounded in 1834 that the forces termed electricity and chemical affinity 
are one and the same, I discussed current views on electrolysis and arrived 
at a conclusion entirely adverse to the explanation put forward by Clausius 
that the conductivity of electrolytes was conditioned by the presence of a 
small proportion of separate ions; this was at a time when the views of 
Arrhenius were not yet spread abroad, although they had been communi- 
cated to the Swedish Academy ; I knew of them only from Ostwald. In 
justice to the attitude of complete antagonism which I have always main- 
tained towards the speculations of the Arrhenius-Ostwald school, I may 
point out here that in drawing attention to the views expressed by 
Arrhenius and Ostwald as to the correlation of chemical with electrolytic 
activity (and I was the first English writer who called attention to them), 
I took occasion to say: ‘ There cannot be a doubt that these investigations 
are of the very highest importance.’ In the interval, Ostwald has charged 
his test-tubes with ink instead of with chemical agents and by means of a 
too facile pen has enticed chemists the world over into becoming adherents 
of the cult of ionic dissociation—a cult the advance of which may well be 
ranked with that of Christian science, so implicit has been the faith of its 
adherents in the doctrines laid down for them, so extreme and narrow the 
views of its advocates. At last, however, the criticism which has been far 
too long delayed is being brought to bear and the absurdity of not a few 
of the propositions which the faith entails is being made evident ; it is to 
be hoped that we shall soon enter on a period in which common sense will 
prevail once more; that ere long an agreement will be arrived at both 
as to the nature of chemical change in general'and as to the conditions 
which determine it. The lesson we shall have learnt will be one of no slight 
import, if it but teach us the ever-present need of questioning our grounds 
of belief, if it serve to bring home to us the danger of uncontrolled literary 
propagandism in science, if it but cause us always to be on our guard 
against the intrusion of authority and of dogmatism into our speculations. 
Before attempting to deal with any of the problems which concerned us 
at Aberdeen I will first briefly pass the more salient features of advance 
in review. Few probably are aware how extraordinary is the command 
we now have of our subject. In 1885, in defending the tendency of chemists 
to devote themselves to the chemistry of carbon, I could speak of the great 
outcome of their labours as being the establishment of the doctrine of 
structure. Everything that has happened in the interval is in support of 
this contention. It is interesting that in a recent lecture* on the Physical 
Aspect of the Atomic Theory, the most prominent living exponent of 
physical theories has given a not unwelcome recognition of our right- 
mindedness in saying: ‘As time goes on it becomes increasingly difficult 
to resist the direct evidence for the simple view that, in many cases, 
chemical combination is not so much a fusion or intermingling of the 
combining atomic structures as rather an arrangement of them alongside 
one another under steady cohesive affinity, the properties of each being 
1 The Wilde Lecture, 1908. By Professor Larmor, Sec.. R.S., Manchester 
Literary and Philosophical Society Memoirs. 
