1822.] Mr. Moyle on an Electrical Phenomenon. 439 
I fear that the best apology which can be offered for the 
length of this memorandum will be found in its date. . It is at 
least seasonable. 
Believe me, my dear Sir, very truly yours, © 
J.J. CONYBEARE. 
_ In looking over Ctesias, I found a curious anticipation of the 
use of conductors for lightning which I do not recollect to have 
seen noticed. He relates that a certain variety of iron is found 
in India, which, when fixed into the ground (ayyvomevos ev tn yx), 
has the power of averting storms and lightnings (apyornpas).* 
I would take this opportunity of correcting an apparent inac- 
cury in my account of V. Biriguccio. He is the first writer 
with whom I am acquainted who mentions manganese by its 
present name. KEarhier writers (as quoted by Beckman) allude to 
its use, but term it magnes, or magnesia. I might have added, 
that Biringuccio is mentioned with respect by Du Fresne and 
Beckman. Allow me to apologize for a few errors of the press 
which have crept into that article (originating, I fear, in the 
indistinctness of my own handwriting): the Italian scholar will 
readily discover and correct them.—J. J.C. 
ih 
: 
ARTICLE V. 
On an Electrical Phenomenon, By M. P. Moyle, Esq. 
(To the Editor of the Annals of Philosophy.) 
SIR, Helston, Nov. 6, 1822. 
Tue following circumstance being new to me, and finding no 
mention made of it by chemical writers, induces me to present 
it to your readers, some of whom it may possibly interest. — 
On constructing a thermometer after the usual manner, with a 
glass tube having an oval base, and after it had been hermetically 
sealed, I found, on the subsidence of the mercury, that the tube 
was not perfectly free from damp, so that some of the mercury 
adhered to its sides, and prevented its regular fall. It is neces- 
sary in this case to subject the tube to the heat of a spirit-lamp 
to expel it; this I did without admitting the air; and when the 
* Ctes, Indica. ‘ut supra, sub initio, 
