1found by our ſeveral marks whereby we
had taken notice of its ſeveral removes, that
it had deſcended about (9/16) of an Inch from the
place where it firſt ſetled, & the other Inch
and (7/16) it had aſcended. And it ſeems pro
bable that the height of the Mercurial Cy
linder would have varied yet more, if the
Experiment had been made in the open
Air and in a long Tube, where the Parti
cles of the Impriſon'd Air, by having
more room to diſplay themſelves in,
might not have had ſo ſtrong a Spring to
work upon the Quick-ſilver with. But for
want both of time and of a competent
quantity of Mercury (which was not to be
procur'd where we then happen'd to be)
we were unable to make any further try
als: which therefore chiefly troubled us,
becauſe we would gladly have try'd an in
genious Experiment which was ſuggeſted
unto us by that excellent Mathematician
Mr. Wren, who being invited to name any
thing he would have us try touching the
preſſure of the Air, deſired us to obſerve
whether or no the Quick-ſilver in a long
Tube would not a little vary its height ac
cording to the Tides, eſpecially about the
New and Full Moon, about which times
Mariners obſerve thoſe great Flowings
and Ebbs of the Sea, that they call the
had taken notice of its ſeveral removes, that
it had deſcended about (9/16) of an Inch from the
place where it firſt ſetled, & the other Inch
and (7/16) it had aſcended. And it ſeems pro
bable that the height of the Mercurial Cy
linder would have varied yet more, if the
Experiment had been made in the open
Air and in a long Tube, where the Parti
cles of the Impriſon'd Air, by having
more room to diſplay themſelves in,
might not have had ſo ſtrong a Spring to
work upon the Quick-ſilver with. But for
want both of time and of a competent
quantity of Mercury (which was not to be
procur'd where we then happen'd to be)
we were unable to make any further try
als: which therefore chiefly troubled us,
becauſe we would gladly have try'd an in
genious Experiment which was ſuggeſted
unto us by that excellent Mathematician
Mr. Wren, who being invited to name any
thing he would have us try touching the
preſſure of the Air, deſired us to obſerve
whether or no the Quick-ſilver in a long
Tube would not a little vary its height ac
cording to the Tides, eſpecially about the
New and Full Moon, about which times
Mariners obſerve thoſe great Flowings
and Ebbs of the Sea, that they call the