1egreſs at the Stop-cock to as much of the
external Air as would come in, the Quick
ſilver was impell'd up almoſt to its firſt
height: I ſay almoſt, becauſe it ſtopt
near a quarter of an Inch beneath the Pa
per mark formerly mention'd; which we
aſcrib'd to this, That there was (as is u
ſual in this Experiment) ſome little Parti
cles of Air engag'd among thoſe of the
Quick-ſilver; which Particles, upon the
deſcent of the Quick-ſilver, did manifeſt
ly riſe up in Bubbles towards the top of
the Tube, and by their preſſure, as well
as by leſſening the Cylinder by as much
room as they formerly took up in it, hin
der'd the Quick-ſilver from regaining its
firſt height.
external Air as would come in, the Quick
ſilver was impell'd up almoſt to its firſt
height: I ſay almoſt, becauſe it ſtopt
near a quarter of an Inch beneath the Pa
per mark formerly mention'd; which we
aſcrib'd to this, That there was (as is u
ſual in this Experiment) ſome little Parti
cles of Air engag'd among thoſe of the
Quick-ſilver; which Particles, upon the
deſcent of the Quick-ſilver, did manifeſt
ly riſe up in Bubbles towards the top of
the Tube, and by their preſſure, as well
as by leſſening the Cylinder by as much
room as they formerly took up in it, hin
der'd the Quick-ſilver from regaining its
firſt height.
This Experiment was a few days after
repeated in the preſence of thoſe excellent
and deſervedly Famous Mathematick
Profeſſors, Dr. Wallis, Dr. Ward, and Mr.
Wren, who were pleaſed to Honor it with
their Preſence: And whom I name, both
as juſtly counting it an Honor to be
known to them, and as being glad of ſuch
Judicious and illuſtrious Witneſſes of our
Experiment; and 'twas by their gueſs that
the top of the Quick-ſilver in the Tube
was defin'd to be brought within an Inch
repeated in the preſence of thoſe excellent
and deſervedly Famous Mathematick
Profeſſors, Dr. Wallis, Dr. Ward, and Mr.
Wren, who were pleaſed to Honor it with
their Preſence: And whom I name, both
as juſtly counting it an Honor to be
known to them, and as being glad of ſuch
Judicious and illuſtrious Witneſſes of our
Experiment; and 'twas by their gueſs that
the top of the Quick-ſilver in the Tube
was defin'd to be brought within an Inch