1of our Learned and Acurate Mathema
ticians, thinking it enough for me to have
given the Hint already ſuggeſted.
ticians, thinking it enough for me to have
given the Hint already ſuggeſted.
For further confirmation of what hath
been delivered, we likewiſe tryed the Ex
periment in a Tube of leſs then two foot
long: and, when there was ſo much Air
drawn out of the Veſſel, that the remain
ing Air was not able to counterballance
the Mercurial Cylinder, the Quick-ſilver
in the Tube ſubſided ſo viſibly, that (the
Experiment being try'd in the little Veſ
ſel lately mention'd) at the firſt ſuck it
fell above a ſpan, and was afterwards
drawn lower and lower for a little while;
and the external Air being let in upon it,
impell'd it up again almoſt to the top of
the Tube: So little matters it how heavy
or light the Cylinder of Quick ſilver to
ſubſide is, provided its gravity over
power the preſſure of as much external
Air as bears upon the ſurface of that Mer
cury into which it is to fall.
been delivered, we likewiſe tryed the Ex
periment in a Tube of leſs then two foot
long: and, when there was ſo much Air
drawn out of the Veſſel, that the remain
ing Air was not able to counterballance
the Mercurial Cylinder, the Quick-ſilver
in the Tube ſubſided ſo viſibly, that (the
Experiment being try'd in the little Veſ
ſel lately mention'd) at the firſt ſuck it
fell above a ſpan, and was afterwards
drawn lower and lower for a little while;
and the external Air being let in upon it,
impell'd it up again almoſt to the top of
the Tube: So little matters it how heavy
or light the Cylinder of Quick ſilver to
ſubſide is, provided its gravity over
power the preſſure of as much external
Air as bears upon the ſurface of that Mer
cury into which it is to fall.
Laſtly we alſo obſerv'd, That if (when
the Mercury in the Tube had been drawn
down, and by an Ingreſs permitted to the
external Air, impell'd up again to its for
mer height) there were ſome more Air
thruſt up by the help of the Pump into
the Mercury in the Tube had been drawn
down, and by an Ingreſs permitted to the
external Air, impell'd up again to its for
mer height) there were ſome more Air
thruſt up by the help of the Pump into