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281
Heroes of the Telegraph
·
John Munro
249
The
microphone
is
a
discovery
as
well
as
an
invention,
and
the
true
explanation
of
its
action
is
as
yet
merely
an
hypothesis.
It
is
supposed
that
the
vibrations
put
the
carbons
in
a
tremor
and
cause
them
to
approach
more
or
less
nearly,
thus
closing
or
opening
the
breach
between
them,
which
is,
as
it
were,
the
floodgate
of
the
current.
The
applications
of
the
microphone
were
soon
of
great
importance.
Dr.
B.
W.
Richardson
succeeded
in
fitting
it
for
auscultation
of
the
heart
and
lungs;
while
Sir
Henry
Thompson
has
effectively
used
it
in
those
surgical
operations,
such
as
probing
wounds
for
bullets
or
fragments
of
bone,
in
which
the
surgeon
has
hitherto
relied
entirely
on
his
delicacy
of
touch
for
detecting
the
jar
of
the
probe
on
the
foreign
body.
There
can
be
no
doubt
that
in
the
science
of
physiology,
in
the
art
of
surgery,
and
in
many
other
walks
of
life,
the
microphone
has
proved
a
valuable
aid.
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