1the heat or cold that affected the ambient
Air. But that which I was chiefly careful
to obſerve, was this, That oftentimes the
Quick-ſilver did riſe and fall in the Tube,
and that very notably, without conforming
it ſelf to what is uſual in Weather-glaſſes,
whoſe Air is at the top, nay quite contrary
thereunto: for ſometimes I obſerv'd it in
very cold weather (ſuch as this Winter has
already afforded us good ſtore of) to fall
down much lower then at other times,
when by reaſon of the abſence of both
Froſt, Snow, and ſharp Winds, the Air was
comparatively much warmer. And I fur
ther obſerv'd, That ſometimes the Quick
ſilver would for ſome days together reſt
almoſt at the ſame height; and at other
times again it would in the compaſs of the
ſame day conſiderably vary its altitude,
though there appear'd no change either in
the Air abroad, or in the temper of the Air
within the Room (wherein was conſtantly
kept a good Fire) nor in any thing elſe, to
which either I, or ſome eminently Learned
Men whom I then acquainted with the
Experiment, could reaſonably impute
ſuch a change: Eſpecially conſidering that
the ſpace wherein the Mercury wandred up
and down, within about five Weeks, a
mounted to full two Inches, of which we
Air. But that which I was chiefly careful
to obſerve, was this, That oftentimes the
Quick-ſilver did riſe and fall in the Tube,
and that very notably, without conforming
it ſelf to what is uſual in Weather-glaſſes,
whoſe Air is at the top, nay quite contrary
thereunto: for ſometimes I obſerv'd it in
very cold weather (ſuch as this Winter has
already afforded us good ſtore of) to fall
down much lower then at other times,
when by reaſon of the abſence of both
Froſt, Snow, and ſharp Winds, the Air was
comparatively much warmer. And I fur
ther obſerv'd, That ſometimes the Quick
ſilver would for ſome days together reſt
almoſt at the ſame height; and at other
times again it would in the compaſs of the
ſame day conſiderably vary its altitude,
though there appear'd no change either in
the Air abroad, or in the temper of the Air
within the Room (wherein was conſtantly
kept a good Fire) nor in any thing elſe, to
which either I, or ſome eminently Learned
Men whom I then acquainted with the
Experiment, could reaſonably impute
ſuch a change: Eſpecially conſidering that
the ſpace wherein the Mercury wandred up
and down, within about five Weeks, a
mounted to full two Inches, of which we