The evening telegraph. [volume] (Philadelphia [Pa.]) 1864-1918, 1867-06-08

with such pOrtentOus fables deter men from
the study Of true causes. Such an effect he
says cannot be produced by magnets, and he
proves the fancy to be an error, ''lest any one
should be deluded by vain hope" Vague
and erroneous though the notions of a tee-
graph then were, they were truer than the
refutaton of Cabeus, grounded on the false
principle that "every physical agent deter
mines for itself certain sphere of activity,
beyond which il cannot have any influence"
But the interesting question remains, to
whom is due the first suggestion that intelli-
genoe may be conveyed by magnetism or cleo
tricity2 Strada attributed it to the celebrated
Cardinal Bembo the Secretary of Leo X But
Bembo, who died in l547, was a historian and
literary character, and would hardly be likely
to form so new a conception of purely scien-
tifc kind.
The earliest work in which we have been
able to trace the description of the supposed
telegraph is the celebrated Natural Magic"
of the Neapolitan Baptista Porta, published in
the year 1889. This work is a collection of all
that was most wonderful in the sciences, then
aroused from long sleep in Italy. His seventh
book is on the "WOnders of the Magnet In
the preface he enumerates these wonders, such
as the mariners compass, the perpetual
motion, and the sympathetic needles. ~ do
not fear," he says, 'that with long absent
friend, even though he be confined by prison
walls, we can communicate what we wish
by means of two compass needles circum-
scribed by the alphabet" A few lines before
we find him mentioning with great respect
Marco Pelo, the source of some of his informa-
tion. But in the eighteenth chapter of the
same book we get more, probably, to the
origin OF the notions in question. The fact that
If magnet be placed beneath a table it will
affect magnetic needle above the table, in
spite OF the intervening matter, is mentioned
by Porta with much wonder. This is the ex-
pertinent which seems to have suggested the
power of two magnetic needles to act upon
each other at distance, even though prison
walls interviewed. And, strange to say, this
experiment may be traced back to the great
St. Augustine. "Novit hoe experimentum
Dlvus Augustinus," says Porta, and an exact
description will accordingly be found in Au-
gustine's treatise, ''De Civitate De, l." a work
believed to have been begun A. d. Alb.
1t is the fashion in these days to fall into
raptures of wonder and exultation over the
magnetic telegraph, but it is not we who have
first wondered. Pliny counted the loadstone
as the most wonderful thing in nature.
"Quid enim mtrabilius?" he asks. "Iron is the
strongest thing in nature, and yet before the
magnet II becomes dOcile." He reflects -
"Cedat ct pdtitT mOreS." All ages, then
have shared in the intelligent wonder excited
by the powers of magnetism. 1t is only the
1per inspections OF this age that have carried
out to the letter the anticipations of former
ages. The telegraph of the present time
tends to assume exclusively the form most
nearly analogous to the conceptions of
Porta. The earliest attempts at electric
telegraph, as Mr.. Dodd well relates, were made
with frictional electricity, which is not appl-
cable to the purpose. Then galvanism was
studied, and the conducting powers of metallic
wire became understood. Now, the most i'm
proved telegraphs consist essentially of a
magnet moved in front of one end of wire,
and magnetic needle which is thereby made
to move in front of the other end of the wire
And though wire is quite indispensable to
conduct magnetic influence in one direction, it
IS fact that the return current passes back
without wire, through land and sea, stayed
neither by wall nor mountain, as Porta ina
yined to himself.
The time is rapidly approaching when
Ariel's girdle will be completed, and signals
be transmitted round the world in a moment.
1t is idle, perhaps, to suggest that Shake
speare may have had some thought of magnetic
when he conceived that fan
tastical idea. Certain it is, however, that the
conceit of space-destroying telegraph was
whispered thorow the world with some at
tention' in his age, and we have thought this
to be a fact worthy of being little better
known.