ANNIVERSARY ADDRESS. 27 
gusty to an unexpected degree. Lord Rayleigh supplied the 
idea of the use of intermittent wind, and the evidence showing 
that winds are, in fact, extremely intermittent has been put 
together by Langley, if not indeed originally discovered by him. 
Before I conclude I should like to make a few remarks on that 
particular branch of physical chemistry in which I am chiefly 
interested. I refer to the electrical properties of substances. 
Both electricity and chemistry are in this state. Neither science 
can make much progress in fundamental principles without the 
assistance of the other. It has long been a truism that when we 
know the nature of electricity, we shall know a little about the 
fundamental mechanism of chemical action and vice versa. The 
extraordinary definitness of the relation between the time integral 
of an electric current and the amount of decomposition in an 
electrolytic cell through which it passes, shows how necessary a 
theory of electricity is to chemistry. Within the last few years 
a number of experimenters have been busy on the passage of 
electric currents through gases, with the result that there is now 
little or no doubt but that gaseous conduction is also electrolytic. 
We have no means of deciding at present whether conduction 
through metals is electrolytic or not, and I shall show, if time 
permits, that with bad conductors the probability is in favour of 
electrolysis, We, therefore, have the fact that, setting metallic 
conductors aside as ambiguous, whenever we get a conduction 
current we get, not only magnetic effects, but chemical effects as 
well ; and any respectable theory of electricity must embrace them. 
We see, therefore, that this road, like all others, leads to our 
requiring to examine the relation between ether and matter, or, 
in other words, all physical roads in the long run lead equally to 
chemistry. It has been my endeavour, therefore, for many years, 
to elucidate some of the relations involved, but I was stopped on 
the threshold of enquiry by the difficulty that the electrical 
Properties of elemental substances with the exception of metals 
Were unknown. With the assistance of Mr. Pollock and two of 
my students, Messrs, Allen and Brearley, I made a beginning by 
