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XXVII. The Bakerian Lecture. On the relations of electrical 
and chemical changes. By Sir Humphry Davy, Bart. 
Pres. R. S. 
Read June 8, 1826. 
I. Introduction. 
A long time has elapsed since I read before this Society 
the Bakerian Lecture on the Chemical Agencies of Electri- 
city. The general laws of decomposition developed in that 
Paper were immediately illustrated by some practical results, 
which the Society did me the honour to receive in a very 
favourable manner ; and which, by offering a class of new 
and powerful agents, led me away for many years into a 
field of pure chemical enquiry : and it is only lately, and on 
an occasion which is well known, that I have again taken up 
the subject of the general principles of electro-chemical 
action. After a number of new experiments, which I shall 
have the pleasure of laying before the Society, and notwith- 
standing the various novel views which have been brought 
forward in this and in other countries, and the great activity 
and extension of science, it is peculiarly satisfactory to me to 
find that I have nothing to alter in the fundamental theory 
laid down in my original communication ; and which, after a 
lapse of twenty years, has continued, as it was in the begin- 
ning, the guide and foundation of all my researches. 
I am the more inclined to bring forward these new labours 
at the present moment, though they are far from being in a 
