This Notion may perhaps be ſome
what further explain'd, by conceiving the
Air near the Earth to be ſuch a heap of
little Bodies, lying one upon another, as
may be reſembled to a Fleece of Wooll.
For this (to omit other likeneſſes betwixt
them) conſiſts of many ſlender and flexi
ble Hairs; each of which, may indeed,
like a little Spring, be eaſily bent or roul
ed up; but will alſo, like a Spring, be
ſtill endeavouring to ſtretch it ſelf out
again. For though both theſe Haires,
and the Aerial Corpuſcles to which we
liken them, do eaſily yield to externall
preſſures; yet each of them (by vertue of
its ſtructure) is endow'd with a Power or
Principle of ſelf-Dilatation; by vertue
whereof, though the hairs may by a Mans
hand be bent and crouded cloſer together,
and into a narrower room then ſuits beſt
with the nature of the Body: Yet whil'ſt
the compreſſion laſts, there is in the fleece
they compoſe an endeavour outwards,
whereby it continually thruſts againſt the
hand that oppoſes its Expanſion. And
upon the removall of the external preſ
ſure, by opening the hand more or leſs, the
compreſſed Wooll does, as it were, ſpon
taneouſly expand or diſplay it ſelf towards
what further explain'd, by conceiving the
Air near the Earth to be ſuch a heap of
little Bodies, lying one upon another, as
may be reſembled to a Fleece of Wooll.
For this (to omit other likeneſſes betwixt
them) conſiſts of many ſlender and flexi
ble Hairs; each of which, may indeed,
like a little Spring, be eaſily bent or roul
ed up; but will alſo, like a Spring, be
ſtill endeavouring to ſtretch it ſelf out
again. For though both theſe Haires,
and the Aerial Corpuſcles to which we
liken them, do eaſily yield to externall
preſſures; yet each of them (by vertue of
its ſtructure) is endow'd with a Power or
Principle of ſelf-Dilatation; by vertue
whereof, though the hairs may by a Mans
hand be bent and crouded cloſer together,
and into a narrower room then ſuits beſt
with the nature of the Body: Yet whil'ſt
the compreſſion laſts, there is in the fleece
they compoſe an endeavour outwards,
whereby it continually thruſts againſt the
hand that oppoſes its Expanſion. And
upon the removall of the external preſ
ſure, by opening the hand more or leſs, the
compreſſed Wooll does, as it were, ſpon
taneouſly expand or diſplay it ſelf towards