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Heroes of the Telegraph
·
John Munro
9
In
1806,
Ralph
Wedgwood
submitted
a
telegraph
based
on
frictional
electricity
to
the
Admiralty,
but
was
told
that
the
semaphore
was
sufficient
for
the
country.
In
a
pamphlet
he
suggested
the
establishment
of
a
telegraph
system
with
public
offices
in
different
centres.
Francis
Ronalds,
in
1816,
brought
a
similar
telegraph
of
his
invention
to
the
notice
of
the
Admiralty,
and
was
politely
informed
that
'telegraphs
of
any
kind
are
now
wholly
unnecessary.'
In
1826-7,
Harrison
Gray
Dyar,
of
New
York,
devised
a
telegraph
in
which
the
spark
was
made
to
stain
the
signals
on
moist
litmus
paper
by
decomposing
nitric
acid;
but
he
had
to
abandon
his
experiments
in
Long
Island
and
fly
the
country,
because
of
a
writ
which
charged
him
with
a
conspiracy
for
carrying
on
secret
communication.
In
1830
Hubert
Recy
published
an
account
of
a
system
of
Teletatodydaxie,
by
which
the
electric
spark
was
to
ignite
alcohol
and
indicate
the
signals
of
a
code.
But
spark
or
frictional
electric
telegraphs
were
destined
to
give
way
to
those
actuated
by
the
voltaic
current,
as
the
chemical
mode
of
signalling
was
superseded
by
the
electro-magnet.
In
1820
the
separate
courses
of
electric
and
magnetic
science
were
united
by
the
connecting
discovery
of
Oersted,
who
found
that
a
wire
conveying
a
current
had
the
power
of
moving
a
compass-needle
to
one
side
or
the
other
according
to
the
direction
of
the
current.
La
Place,
the
illustrious
mathematician,
at
once
saw
that
this
fact
could
be
utilised
as
a
telegraph,
and
Ampere,
acting
on
his
suggestion,
published
a
feasible
plan.
Before
the
year
was
out,
Schweigger,
of
Halle,
multiplied
the
influence
of
the
current
on
the
needle
by
coiling
the
wire
about
it.
Ten
years
later,
Ritchie
improved
on
Ampere's
method,
and
exhibited
a
model
at
the
Royal
Institution,
London.
About
the
same
time,
Baron
Pawel
Schilling,
a
Russian
nobleman,
still
further
modified
it,
and
the
Emperor
Nicholas
decreed
the
erection
of
a
line
from
Cronstadt
to
St.
Petersburg,
with
a
cable
in
the
Gulf
of
Finland
but
Schilling
died
in
1837,
and
the
project
was
never
realised.
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