[ 393 1 
3°. When the inner flocking was drawn out, and 
applied to the outfide of the other, they lifted one 
pound and three quarters ; that is, between ten and 
eleven times the weight of the white flocking *. 
It is not my defign to draw any conclufions from 
thefe experiments, and much lefs to determine how 
far electrical cohefion may ferve, as a principle, to 
to account for many remarkable appearances in na- 
ture. I relate the experiments I have been witnefs to, 
by way of fupplement to Mr. Symmer’s third paper; 
and I conlider the refult of them, only, as a farther 
proof of the furprifing degree, to which a power in. 
eleCtricity, which had not before been attended to, 
may be carried, in even the flighted: fubflances, thole 
of white and of black filk. I am, Sir, 
Your mofl obedient, humble fervant, 
Kew, December 18,1759. John Mitchell* 
* In the third of thefe papers I obferved, that {lockings electri- 
fied, and applied to one another externally, cohered with a force 
greater or lefs, according to the manner in which they joined in 
contaCl with each other. This appears to be the reafon, why the 
ftockings here made ufe of, being much lefs pliable than the thinner 
kind, do not, in external cohefion, raife a weight fo great in pro- 
portion as thofe do. From thence I fancied, that if the {lockings 
of fpun filk Ihould be firft allowed to come together, and after- 
wards be preffed clofe between one’s hands, their cohefion externally 
with one another would thereby be much improved : Accordingly, 
upon repeated trials, I found, that the white Hocking, when thus 
preffed to the black in external contaCl, was capable of raifing be- 
tween three and four pounds; that is, about twenty-two times its 
own weight. 
I have taken the liberty to fubjoin thefe few obfervations, by way 
of notes, to Dr. Mitchell’s letter, as they relate to the fame fubjeCl, 
and contain matter, which has occurred fince his letter was read in 
the Society. 
February ift, 1760. R- Symmer. 
Vol LI. Eee XXXVII. 
