Intelligence and Miscellaneous Articles. 157 
Coulombian theory. In Mr. Thomson’s paper, Phil. Mag. for 1854, 
vol. vii. p. 193, I observe the following remark :—‘ The amount of 
heat is proportional to the square of the quantity discharged, as was 
first demonstrated by Joule, although it had been announced by Sir 
Snow Harris, as an experimental result, to be simply proportional to 
the quantity.” Riess, Joule, and Clausius appear to agree as to my 
having made this announcement, and confidently allude to the inac- 
curacy and to the refutation of my deductions. Now I do here most 
emphatically and most positively deny, ever having stated anything of 
the kind; but since these gentlemen say I have done so, and pre- 
tend to have corrected my error, I call upon them as a point of 
honour to say when I made such an announcement, or where in 
any of my published works it is to be found. The fact is, that so 
far from having stated the law of electrical heat to be simply as the 
quantity of electricity discharged, I was really the first to discover 
with precision, and demonstrate with exactitude, the law in question ; 
and that, too, long before Mr. Thomson and the other gentlemen 
above mentioned were at all known in the world of science. If Mr. 
Thomson will turn to pages’67 and 68 of the Transactions of the 
Plymouth Institution, published in 1830, and quoted in the Journal 
of the Royal Institution, 1830-31, p.380*, he will find in the former 
work a series of original experiments on the heating effects of the 
electrical discharge, and at page 68 the following announcement :— 
“It may be hence inferred that the effects of an electrical discharge 
on a metallic wire, all other things remaining the same, is directly 
as the square of the quantity.” See also Journal of Royal Institu- 
tion, p. 381 (vi.). Moreover the date of my paper is so far back 
as November 1825; and I may say in the words of Dr. Riess 
(Phil. Mag. 1854, vol. vii. p. 348), that ‘‘ an assertion of such a 
general character as that ventured by Mr. Thomson ought to be the 
consequence of a careful examination,” especially of what has been 
done at home. 
As this subject is of importance, I may further remark, that the 
experiments of Cuthbertson and others, referred to by Becquerel and 
quoted by Joule, Phil. Mag. October 1841, can scarcely be said to 
have established the law in question, or evenits probability. In the 
first place, they had no accurate measure of the quantity of electri- 
city accumulated; they were unaware that twice the quantity accu- 
mulated on a given coated surface would counterpoise four times the 
weight, regulating Cuthbertson’s own steel-yard electrometer, in 
which, a charge of 30 grains was taken as twice that of 15 grains. 
Their methods of research by the fusion of wires appears to have been 
anything but exact, and all sorts of tricks were played with the bat- 
tery, as by breathing into the jars, &c. Cuthbertson says, ‘ Practical 
Electricity,’ pp. 180 to 186, ‘‘If 18 inches of wire be taken and a 
given charge just causes it to run into balls, mych shorter lengths 
will still be only converted into balls; if only 7 inches be taken, 
nothing but balls will appear; the only difference will be that the 
balls will be smaller, and will be dispersed to a greater distance, 
* See also a copy of my paper printed in 1828, in the Library of the 
Royal Society. 
