[ 39 ^ ] 
by Mr. Symmer in his third paper : that is, we found, 
that when the white flocking was put within the 
black, or vice verfd , and both highly electrified, 
taking hold of the one, while a fcale with weights 
was put to the other, we could raife feventeen ounces 
before the (lockings feparated. 
We then repeated one or two of thofe experiments 
with fome little variation of circumflances. We 
turned one of the (lockings infide out, and put that 
within the other : the inner or rough Tides of the 
ftockings being thus together, by which means they 
took fader hold of each other, we now found, that 
it required the weight of twenty ounces to feparate 
them. 
When the dockings were feparated, and applied 
externally to each other, they then raifed the weight 
of ten ounces *. 
We 
* Some time after this letter of Dr. Mitchell’s had been read in 
the Society, as I was of opinion, that the thin ftockings, mentioned 
above, had loft much of their electrical power ftnee the beginning 
. of April laft, when they firft had been made ufe of in experiments, 
and that it was owing to the peculiar influence of the weather, that 
they raifed as great a weight now as they had done then, I had 
the black new dyed, and the white wafhed, and afterwards whit- 
ened in the fumes of fulphur. Upon this, I found their force very 
much increafed. On the 9th of January, the weather being much 
in the fame ftate as it had been the 15th of the preceding month, 
the ftockings, thus prepared, and put one within another, having 
their rough Tides together, lifted no lefs than three pounds and three 
ounces before they feparated. Dr. Mitchell was like wife prefent at 
this experiment. 
How far the circumftance of fmoking the white flocking in the 
fumes of fulphur, might have contributed to increafe the eleCtrical 
power, is what I cannot take upon me to fay. I fhould think, 
however, that it does not much contribute to it ; for we find, by 
the experiments in the fequel of this letter, that the force of cohe- 
