1ſtopple may be lifted up without any dif
ficulty at all.
ficulty at all.
By ſeveral other of the Experiments
afforded us by our Engine, the ſame no
tion of the great and equal preſſure of the
free Air upon the Bodies it environs,
might be here manifeſted, but that we
think it not ſo fit to anticipate ſuch Ex
periments: And therefore ſhall rather
employ a few lines to clear up a difficulty
touching this matter, which we have ob
ſerv'd to have troubled ſome even of the
Philoſophical and Mathematical Specta
tors of our Engine, who have wonder'd
that we ſhould talk of the Air exquiſitely
ſhut up in our Receiver, as if it were all
one with the preſſure of the Atmoſphere;
whereas the thick and cloſe body of the
Glaſs, wholly impervious to the Air, does
manifeſtly keep the incumbent Pillar of
the Atmoſphere from preſſing in the leaſt
upon the Air within the Glaſs, which it
can no where come to touch. To eluci
date a little this matter, let us conſider,
That if a man ſhould take a fleece of
Wool, and having firſt by compreſſing it
in his hand reduc'd it into a narrower com
paſs, ſhould nimbly convey and ſhut it
cloſe up into a Box juſt fit for it, though
afforded us by our Engine, the ſame no
tion of the great and equal preſſure of the
free Air upon the Bodies it environs,
might be here manifeſted, but that we
think it not ſo fit to anticipate ſuch Ex
periments: And therefore ſhall rather
employ a few lines to clear up a difficulty
touching this matter, which we have ob
ſerv'd to have troubled ſome even of the
Philoſophical and Mathematical Specta
tors of our Engine, who have wonder'd
that we ſhould talk of the Air exquiſitely
ſhut up in our Receiver, as if it were all
one with the preſſure of the Atmoſphere;
whereas the thick and cloſe body of the
Glaſs, wholly impervious to the Air, does
manifeſtly keep the incumbent Pillar of
the Atmoſphere from preſſing in the leaſt
upon the Air within the Glaſs, which it
can no where come to touch. To eluci
date a little this matter, let us conſider,
That if a man ſhould take a fleece of
Wool, and having firſt by compreſſing it
in his hand reduc'd it into a narrower com
paſs, ſhould nimbly convey and ſhut it
cloſe up into a Box juſt fit for it, though