[ 46o ] 
kept longer in the fame heat, it wiil become a non- 
conductor entirely. 
In making the above experiments, I ufed the little 
electrometer, which I have defcribed in the forty- 
eighth volume of the Philofophical TranfaCtions, 
p. 783, and fupported it by fealing-wax, or warm 
glafs. # 
I well remember your acquainting me, that Mr. 
Deiaval did not approve of the above manner of ac- 
counting for his experiment on tobacco-pipe, foon 
after you related it to him, which was fome time lad 
fummer : but as it dill appears fatisfadory to me, 
notwithdanding what that gentleman has lately offered 
againd it (2), your laying it before the Royal Society 
will oblige. 
Dear Sir, 
I ■ | * 
Your mod: obedient 
and mod humble fervant, 
Spitai-Square, John Canton. 
January 21, 1702. J 
(2) See a Letter from Mr. Deiaval to Mr. Wilfon, in the 
firft part of the fifty-fecond volume of the Philofophical Tranl- 
adions. 
