1to think by ſeveral Circumſtances. For
when an eminent Mathematician, and ex
cellent Experimenter, had taken great
pains and ſpent much time in accuratly fil
ling up a Tube of Mercury, we found
that yet there remain'd ſtore of inconſpi
cuous bubbles, by inverting the Tube,
letting the Quick-ſilver fall to its wonted
heighth; and by approaching (by de
grees) a red hot Iron to the out-ſide of the
Tube, over againſt the upper part of the
Mercurial Cylinder, for hereby the little
unheeded bubbles, being mightily expan
ded, aſcended in ſuch numbers, and ſo faſt
to the deſerted ſpace, that the upper part
of the Quick-ſilver ſeem'd, to our wonder,
to boyl. We further obſerv'd, That in
the tryals of the Torricellian Experiment
we have ſeen made by others, and (one
excepted) all our own, we never found that
upon the inclining of the Tube the Quick
ſilver would fully reach to the very top of
the ſeal'd end: which argued, that there
was ſome Air retreated thither that kept
the Mercury out of the unrepleniſh'd
ſpace.
when an eminent Mathematician, and ex
cellent Experimenter, had taken great
pains and ſpent much time in accuratly fil
ling up a Tube of Mercury, we found
that yet there remain'd ſtore of inconſpi
cuous bubbles, by inverting the Tube,
letting the Quick-ſilver fall to its wonted
heighth; and by approaching (by de
grees) a red hot Iron to the out-ſide of the
Tube, over againſt the upper part of the
Mercurial Cylinder, for hereby the little
unheeded bubbles, being mightily expan
ded, aſcended in ſuch numbers, and ſo faſt
to the deſerted ſpace, that the upper part
of the Quick-ſilver ſeem'd, to our wonder,
to boyl. We further obſerv'd, That in
the tryals of the Torricellian Experiment
we have ſeen made by others, and (one
excepted) all our own, we never found that
upon the inclining of the Tube the Quick
ſilver would fully reach to the very top of
the ſeal'd end: which argued, that there
was ſome Air retreated thither that kept
the Mercury out of the unrepleniſh'd
ſpace.
If Your Lordſhip ſhould now demand
what are the beſt expedients to hinder the
intruſion of the Air in this Experiment;
what are the beſt expedients to hinder the
intruſion of the Air in this Experiment;