TtlKORV OF GALVANISM. 
97 
nical power, therefore, properly speaking, is me«surr,.J by Cases of diffi-’ 
the whole of the mechanical effect produced, whether that of 
effect is produced in a greater or lesser time*.” F rom the 
context it is obvious, that by “ the uniform contlnua. tee of the 
same mechanical power, " he means a continuance of an uniform 
pressure moving through equal spaces in equal tiroes, and he 
considers that to be a perfect uniformity of action.. 
[To be continued ) 
• III. 
The Theories of the Excitement of Galvanic Electricity ex- 
plained in Mr. JVilUam Henry's Paper , compared with the 
Phenomena of the Electric Column. By J. A. De Luc, 
F. R. S. &c. 
To IP'illiam Nicholson, Esq. 
SIR, 
Y our valuable Journal is bex:ome the repository of the 
progress of the electric science, and of the opinions on 
the agency of the electric fluid in various phenomena. In par- ^a*»anfc*^elfc- 
ticular you have favoured me with the publication of many of 
^ . plu'iiomcna of 
my papers concerning that science, to which papers I must first the electrio 
refer, as a necessary introduction to the subject announced in 
the above title. 
Your number for June, ISIO, contained the first part of my 
Analysis of the galvanic Pile. Having followed this analysis 
by a long series of experiments, I discovered in this apparatus 
two different operations which deserved to be thoroughly inves- 
tigated. 
The experiments which I had made for the purpose of fol- 
lowing up this first step, were the subject of my paper in your 
number for August, in the same year. These experiments, 
made on the galvanic pile itself, manifested it clearly in two 
distinct operations j one, from which originate all the effects of 
that apparatus, is to set in motion a certain quantity of electric 
fluid, which motion is produced simply by the association, in 
• Phil. Trans. 1776, p. 473. 
sue- 
