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281
Heroes of the Telegraph
·
John Munro
3
Let
us,
therefore,
trace
in
a
rapid
manner
the
history
of
the
electric
telegraph
from
the
earliest
times.
The
sources
of
a
river
are
lost
in
the
clouds
of
the
mountain,
but
it
is
usual
to
derive
its
waters
from
the
lakes
or
springs
which
are
its
fountain-head.
In
the
same
way
the
origins
of
our
knowledge
of
electricity
and
magnetism
are
lost
in
the
mists
of
antiquity,
but
there
are
two
facts
which
have
come
to
be
regarded
as
the
starting-points
of
the
science.
It
was
known
to
the
ancients
at
least
600
years
before
Christ,
that
a
piece
of
amber
when
excited
by
rubbing
would
attract
straws,
and
that
a
lump
of
lodestone
had
the
property
of
drawing
iron.
Both
facts
were
probably
ascertained
by
chance.
Humboldt
informs
us
that
he
saw
an
Indian
child
of
the
Orinoco
rubbing
the
seed
of
a
trailing
plant
to
make
it
attract
the
wild
cotton;
and,
perhaps,
a
prehistoric
tribesman
of
the
Baltic
or
the
plains
of
Sicily
found
in
the
yellow
stone
he
had
polished
the
mysterious
power
of
collecting
dust.
A
Greek
legend
tells
us
that
the
lodestone
was
discovered
by
Magnes,
a
shepherd
who
found
his
crook
attracted
by
the
rock.
However
this
may
be,
we
are
told
that
Thales
of
Miletus
attributed
the
attractive
properties
of
the
amber
and
the
lodestone
to
a
soul
within
them.
The
name
Electricity
is
derived
from
ELEKTRON,
the
Greek
for
amber,
and
Magnetism
from
Magnes,
the
name
of
the
shepherd,
or,
more
likely,
from
the
city
of
Magnesia,
in
Lydia,
where
the
stone
occurred.
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