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.
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