(1X67) 
Attrition, Likewife between every Bead was tfd over a 
String from Pin to Pin, which were fo many pieces of 
fmall Wire, drove thro the Wood for their better fecurity 
and faftnefs, the Beads appearing about half their Diameter 
beyond the Wood to which they were fixt. (as in F^g. 2,) 
In this manner k was put on the Spindle, and faften'd there 
by the two Nutts, as before defcrib'd, ( See Fig, 5. ) Then 
the Brafs Plate on which the Woollen was wrapt, being 
fcrew'd to its place, ( by means of the Socket, which re* 
ceives the lower point of the Spindle) would then (prin^ 
back, and embrace the Amber with a moderate force. ( s 
inJF%.3.) Thu$ prepared, and the Receiver plac'd over, 
with its upper Plate and Box for the Spindle to pafs through, 
the Pump was fet on work, and in a very little time the 
Mercury in tke Gage was elevated to about 29 inches and a 
half, which fliew'd the Recipient to be well exhaufted of 
its Air, The Great Wheel being then turii'd, gave a very 
fwift Attrition of the Amber on the Woollen, but no Light 
at firil appeared ; Yet in a (econd or two of time it became 
vifible enough 5 which (hews it requires fome degrees of 
Heat«to produce the Phdenomenon. I could not obferve that 
the Continuance or Encreafe of the Motion, did contribute 
any thing to the Enhancemerit of the Light, after the ii-:t 
prodaftion of it : Nor would the Light tkus produced. In e 
on the Amber to continue a Circle, notwithftanding rhe 
velocity of the Motion given 5 but dy'd fo foon as ir had 
deferred the Affricated Woollen. However, on the Woci- 
len, (during the Motion, ) where the Attrition of the An- 
ber was made, the Light continud without InrcraiifFi . 
and was difctrnible at three or four foot diftance. VVi) as 
farther to be taken notice of in this Experiment was, Th^t 
it highly Corro lorares and Confirms thofe ma 1e O'V ^he 
Produftien oi Heat in Vacuo by Aimtion : For the A 
was not only m A-ratcly heated, but appear d to be 
and crackt by the Intenfenefs of ir. And the W o 
Hhhhhhhhhhhhh 3 :^ 
