1per, hinders it from falling, as we have
elſewhere more fully declar'd. Upon
theſe grounds we conjectur'd that in caſe
we could procure two marbles exactly
ground to one another; and in caſe we
could alſo ſufficiently evacuate our Re
ceiver, the lower ſtone would, for want
of the wonted and ſuſtaining preſſure of
the Air, fall from the upper. But the
further tryal of this Experiment we muſt,
unleſs your Lordſhip think it worth Your
making at Paris, put off till a fitter
opportunity. For where we now are, we
cannot procure marbles ſo exactly ground,
that they will ſuſtaine one another in the
Air, above a minute or two, which is a
much ſhorter time than the emptying of
our Receiver requires. We did indeed
try to make our marbles ſtick cloſe to
gether by moiſtening their polliſhed ſur
faces with rectifi'd ſpirit of Wine, in re
gard that Liquor by its ſudden avolation
from marble, if powr'd thereon, without
leaving it moiſt or leſs ſmooth, ſeem'd
unable to ſuſtaine them together after the
manner of a glutinous body, and yet
ſeem'd ſufficient to exclude and keep out
the Air. But this we try'd to little pur
poſe, for having convey'd into the Recei-
elſewhere more fully declar'd. Upon
theſe grounds we conjectur'd that in caſe
we could procure two marbles exactly
ground to one another; and in caſe we
could alſo ſufficiently evacuate our Re
ceiver, the lower ſtone would, for want
of the wonted and ſuſtaining preſſure of
the Air, fall from the upper. But the
further tryal of this Experiment we muſt,
unleſs your Lordſhip think it worth Your
making at Paris, put off till a fitter
opportunity. For where we now are, we
cannot procure marbles ſo exactly ground,
that they will ſuſtaine one another in the
Air, above a minute or two, which is a
much ſhorter time than the emptying of
our Receiver requires. We did indeed
try to make our marbles ſtick cloſe to
gether by moiſtening their polliſhed ſur
faces with rectifi'd ſpirit of Wine, in re
gard that Liquor by its ſudden avolation
from marble, if powr'd thereon, without
leaving it moiſt or leſs ſmooth, ſeem'd
unable to ſuſtaine them together after the
manner of a glutinous body, and yet
ſeem'd ſufficient to exclude and keep out
the Air. But this we try'd to little pur
poſe, for having convey'd into the Recei-