1other pneumatical Engines wherein the
Air has been compreſſ'd, and its Springs
violently bent by an apparent externall
force; upon the removall of which, 'tis
no wonder that the Air ſhould, by the
motion of reſtitution, expand it ſelf till
it have recovered its more natural dimen
ſions: whereas in our above-mentioned
firſt Experiment, and in almoſt all others
tryable in our Engine, it appears not
that any compreſſion of the Air prece
ded its ſpontaneous Dilatation or Expan
ſion of it ſelf. To remove this difficul
ty, I muſt deſire Your Lordſhip to take
notice, that of whatever nature the Air,
very remote from the Earth, may be, and
whatever the Schools may confidently
teach to the contrary, yet we have divers
Experiments to evince, that the Atmoſ
phere we live in is not (otherwiſe then
comparatively to more ponderous Bodies)
light, but heavy: And did not their
gravity hinder them, it appears not why
the ſteams of the Terraqueous Globe, of
which our Air in great part conſiſts,
ſhould not riſe much higher then the Re
fraction of the Sun, and other Stars
give men ground to think, that the At
moſphere, even in the judgement of thoſe
Air has been compreſſ'd, and its Springs
violently bent by an apparent externall
force; upon the removall of which, 'tis
no wonder that the Air ſhould, by the
motion of reſtitution, expand it ſelf till
it have recovered its more natural dimen
ſions: whereas in our above-mentioned
firſt Experiment, and in almoſt all others
tryable in our Engine, it appears not
that any compreſſion of the Air prece
ded its ſpontaneous Dilatation or Expan
ſion of it ſelf. To remove this difficul
ty, I muſt deſire Your Lordſhip to take
notice, that of whatever nature the Air,
very remote from the Earth, may be, and
whatever the Schools may confidently
teach to the contrary, yet we have divers
Experiments to evince, that the Atmoſ
phere we live in is not (otherwiſe then
comparatively to more ponderous Bodies)
light, but heavy: And did not their
gravity hinder them, it appears not why
the ſteams of the Terraqueous Globe, of
which our Air in great part conſiſts,
ſhould not riſe much higher then the Re
fraction of the Sun, and other Stars
give men ground to think, that the At
moſphere, even in the judgement of thoſe