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Heroes of the Telegraph
·
John Munro
41
According
to
his
own
statement,
he
devised
the
relay
in
1836
or
earlier;
but
it
was
not
until
the
beginning
of
1837
that
he
explained
the
device,
and
showed
the
working
of
his
apparatus
to
his
friend,
Mr.
Leonard
D.
Gale,
Professor
of
Chemistry
in
the
University.
This
gentleman
took
a
lively
interest
in
the
apparatus,
and
proved
a
generous
ally
of
the
inventor.
Until
then
Morse
had
only
tried
his
recorder
on
a
few
yards
of
wire,
the
battery
was
a
single
pair
of
plates,
and
the
electro-magnet
was
of
the
elementary
sort
employed
by
Moll,
and
illustrated
in
the
older
books.
The
artist,
indeed,
was
very
ignorant
of
what
had
been
done
by
other
electricians;
and
Professor
Gale
was
able
to
enlighten
him.
When
Gale
acquainted
him
with
some
results
in
telegraphing
obtained
by
Mr.
Barlow,
he
said
he
was
not
aware
that
anyone
had
even
conceived
the
notion
of
using
the
magnet
for
such
a
purpose.
The
researches
of
Professor
Joseph
Henry
on
the
electro-magnet,
in
1830,
were
equally
unknown
to
Morse,
until
Professor
Gale
drew
his
attention
to
them,
and
in
accordance
with
the
results,
suggested
that
the
simple
electro-magnet,
with
a
few
turns
of
thick
wire
which
he
employed,
should
be
replaced
by
one
having
a
coil
of
long
thin
wire.
By
this
change
a
much
feebler
current
would
be
able
to
excite
the
magnet,
and
the
recorder
would
mark
through
a
greater
length
of
line.
Henry
himself,
in
1832,
had
devised
a
telegraph
similar
to
that
of
Morse,
and
signalled
through
a
mile
of
wire,
by
causing
the
armature
of
his
electro-magnet
to
strike
a
bell.
This
was
virtually
the
first
electro-magnetic
acoustic
telegraph.[AMERICAN
JOURNAL
OF
SCIENCE.]
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