C 346 ] 
II. 
SIR, 
I N the laft Paper I had the Honour of communi- 
cating to you, I endeavoured to make it appear, 
that the rotatory Motion of glafs Tubes about their 
Axes , before a Fire, was not owing to the Draught 
of the Chimney. In this, I beg Leave firft to men- 
tion an Experiment or two, to {hew that the Mo- 
tion is not owing to any Attraction or Repulfion in 
the Tubes ; and then give the Solution I propofed 
in my laft, but deferred laying before you, becaufe 
my Paper was already carried to too great a Length. 
I fufpended two Fragments of fmall Tubes, 8 
Inches long, and about 7— of an Inch in Diameter, 
near the Fire, from two Pins, by blue Silk Lines, 
which had each a Loop at one End, were tied at 
the other to the Top of the Tubes, and hindered 
from {lipping offby a little Sealing-wax. The Tubes 
came together at the upper End, and receded mani- 
fefily from bach other at the lower, appearing to be 
in a State of Attraction above, and a State of Repul- 
iion below : Bur, fufpeCting this to be owing to the 
Sealing-wax, which foon began to melt, I fcraped 
it off both, leaving only as little as was poftible, to 
hinder the Silks from flipping. The Confequence 
then was, they came together at the lower Ends, and 
very near fo at the upper 5 and, when fufpended from 
one Pin, fo that the Loops of the Silks touch’d each 
other, the Tubes feemfd equally clofe all the Way 
down, without any Appearance either of Attraction 
or Repulfion. But, imagining ftill that a repulfive 
Power 
