1turn'd the Key and ſtopt the Valve, yet we
could plainly hear the noiſe made by the
ballance, though we held our Ears ſome
times at two Foot diſtance from the out
ſide of the Receiver. And this Experi
ment being reiterated in another place,
ſucceded after the like manner. Which
ſeems to prove, that whether or no the
Air be the onely, it is at leaſt, the princi
pal medium of Sounds. And by the way
it is very well worth noting, that in a Veſ
ſel ſo well cloſ'd as our Receiver, ſo weak
a pulſe as that of the ballance of a Watch
ſhould propagate a motion to the Ear in a
Phiſically ſtraight Line, notwithſtanding
the interpoſition of ſo cloſe a Body as
Glaſs, eſpecially Glaſs of ſuch thickneſs
as that of our Receiver; ſince by this it
ſeems that the air impriſon'd in the Glaſs,
muſt, by the motion of the ballance, be
made to beat againſt the concave part of
the Receiver, ſtrongly enough to make
its convex part beat upon the contiguous
Air, and ſo propagate the motion to the
Liſtners ears. I know this cannot but
ſeem ſtrange to thoſe, who, with an emi
nent Modern Philoſopher, will not allow
that a Sound, made in the cavity of a
Room, or other place ſo cloſ'd, that there
could plainly hear the noiſe made by the
ballance, though we held our Ears ſome
times at two Foot diſtance from the out
ſide of the Receiver. And this Experi
ment being reiterated in another place,
ſucceded after the like manner. Which
ſeems to prove, that whether or no the
Air be the onely, it is at leaſt, the princi
pal medium of Sounds. And by the way
it is very well worth noting, that in a Veſ
ſel ſo well cloſ'd as our Receiver, ſo weak
a pulſe as that of the ballance of a Watch
ſhould propagate a motion to the Ear in a
Phiſically ſtraight Line, notwithſtanding
the interpoſition of ſo cloſe a Body as
Glaſs, eſpecially Glaſs of ſuch thickneſs
as that of our Receiver; ſince by this it
ſeems that the air impriſon'd in the Glaſs,
muſt, by the motion of the ballance, be
made to beat againſt the concave part of
the Receiver, ſtrongly enough to make
its convex part beat upon the contiguous
Air, and ſo propagate the motion to the
Liſtners ears. I know this cannot but
ſeem ſtrange to thoſe, who, with an emi
nent Modern Philoſopher, will not allow
that a Sound, made in the cavity of a
Room, or other place ſo cloſ'd, that there
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