On Electricity. 21 
Had I then imagined that the “opinions and suppositions”’ with 
which they were accompanied were intended to form the basis 
of a new system of “ chemical philosophy,” or to be followed by 
the luminous views of electrical combustion, and oxygen and 
hydrogen electricity, which have been developed (at page 267 
of the forty-second volume of the Philosophical Magazine), I 
should certainly have avoided any notice of those ‘‘ statements,” 
and most probably might not then have incurred the anger Mr, 
Walker has manifested against me in his note published in the 
last volume of this Magazine *. ; 
it would be unnecessary to reply to that note, but that it con- 
tains an assertion of “ the thing which is not.” I am repre- 
sented as having asserted that Mr. Walker is in error, without 
adducing one fact to prove it. ‘To refute this misrepresentation, 
ft is only necessary to repeat here my former paragraph, from 
which’ Mr. W. has made some mutilated extracts. It was printed 
as follows: 
“ With respect to the permanence of the effects produced by 
electrical influence, Mr. W. has fallen into error by confounding 
them with communicated electricity. If, after bringing an elee- 
trified body near an insulated conductor, on withdrawing it the 
_ insulated conductor remains permanently electrified, it must 
have lost or received electricity; and in either case it is electri- 
fied by communication, and not by position, whether its loss or 
gain be the consequence of the contact of some conducting 
body, or the imperfection of its own insulation during the disturb- 
ance of its natural electricity; and one of these causes must 
operate to produce permanent electricity in such an experiment : 
for neither an insulated rod, nor a gold-leaf electrometer, if 
properly constructed, will be permanently electrified by approxi- 
mation to an electrified body; unless they communicate by im- 
perfect insulation, or pointed terminations, with surrounding 
unelectrified substances during such approximation. 'These are 
facts, which the constant repetition of such experiments pro- 
fessionally enables me to state with confidence; and they are 
indeed such as amongst electricians are generally admitted: but 
perhaps Mr. Walker has yet to learn, that a conducting body 
supported by dry glass, and surrounded by dry air, may be still 
very far from perfectly insulated +.” 
The statement in the preceding paragraph may be verified in 
a few minutes by any one sufficiently acquainted with the practice 
of electricity to make experiments with due accuracy; and ] 
believe it not only adduces a fact in proof of Mr. Walker’s error, 
put offers the requisite information to show him its cause, 
* Vol, xlii. p. 485. t Phil. Mag, vol. xli!. p. 264. 
B8 Independent 
