( 590 ) 
clear and conveniently fhaped Glafs, that the long Stem or Pipe 
being To far filled with Jfiuickfilver , as that there might be about 
halfa fpoonfulof Air leftattheclofed End, where the Wood was 
placed, it might be invertedinto a little Glafs of Stagnant fihAck- 
filver , and therewith conveyed into a flender Receiver , out of 
which as the Air fhould come to be pumped, that included in the 
Glafs, which held the Wood, might be rarificd, and afterwards 
upon the admiffion of the outward vfir (which muff impell up the 
Jguickfiher to its former height) might bereftored to ics former 
ftate. But when we came to make trial of this, we had no Recei- 
ver conveniently fhaped, that was fo clear and thin, as that we 
could fee the Wood (bine through both the Glaffes, And though 
we would for an Expedient have fuhftimted a fine thin gladder, 
wherein the Wood was to be put, and a convenient quantity of 
Air ftrongly tied up with it, yet for want of a flladdei fine enough 
for our turn, that Expedient alfo proved ufelefs to us. .gut being 
defirous to make what trial we could by the lead unfit means, we 
had in our power, we got an old, but thin Glafs, fealed atone 
end, whofe fhape was pretty Cylindrical, and whofe bore was about 
the bigr.efsofa mans little finger, and whofe length was about a 
foot or more. Into this Pipe near the fealed end we put a piece of 
Shining Wood, wedged in with a piece of Cork to keep ic from 
falling ^ and having inverted the nofeof it into another flender 
Glafs, but not Cylindrical, wherein was pretty fto:e of 
ver, we put them both into a long Receiver , fhaped almoftlikea 
Glaf Chrtrn 0 and having pumped a whil i, that the Air included 
in the Pipe, expanding it felt, might deprefs the Jjtuick fiber, and 
fo make efcapes into the Receiver , as long as we thought fit $ we 
then let in the outward Air, that the fiagnant £)ujckfilver might 
be impelled into the cavity of the Pipe now freed from much of 
the Air, to the height requifite for our purpofe. 
This done, we plied the Pump again, and obferved, That, as 
the Air in the Pipe did by its own Spring exoand it felf more 
and more, and grow thinner and thinner, the shining Wood grew 
dimmer and dimmer,, till at length it ceafed to fhine, the inter- 
nal Air being then got a good way lower, than the iurface of 
the external Quickfilver : whereupon opening the commerce be- 
tween the cavity of the Receiver , and th zAtmofiphcre^ the Quick- 
1 • lilver 
