f which was made of iron, lying against a rock. On awaking,
and rising to depart, he found, when he attempted to take up his crook,
that the iron adhered to the rock. Having communicated this
extraordinary fact to some neighbouring philosophers, they called the
rock after the name of the shepherd, Magnes, the magnet.

The Chinese, of still more ancient date, so their traditions affirm,
discovered a mountain rising out of the sea possessing an intensity of
attraction so great that the nails and iron bands were drawn out of
their ships, causing their immediate wreck. Those sea-arabs whom we
call Phoenicians had, at a very early date, made use of their knowledge
of the property of the loadstone to turn towards the North Pole; though,
like many other discoveries, as I have just mentioned, it was kept a
profound secret among a select few, and concealed from the public by
having an air of religious mystery thrown over it. Lumps of loadstone
formed into balls were preserved in their temples, and looked upon with
awe, as possessing mystic properties. With these round stones the point
of a needle was rubbed, as often as it required fresh magnetising.

I have already described the compass used by the Phoenicians, and how,
long after Islamism had gained the ascendency, it was possessed by their
descendants. At length the secret was divulged, and it came into
general use among the mariners of the Mediterranean in the tenth and
eleventh centuries. Its original form was unaltered for nearly four
centuries, when, in 1502, Flavio Gioja of Positano, near the town of
Amalfi, on the coast of Calabria, a place celebrated for its maritime
enterprise, improved upon the primitive rude and simple instrument by
suspending the needle on a centre, and enclosing it in a box. The
advantages of his invention were so great that his instrument was
universally adopted, and hence he gained the credit of being the
inventor of the mariner's compass, of which he was only the improver.

Long before the compass was used at sea, it had been employed by the
Chinese to direct the course of their caravans across the desert. For
this purpose a figure, placed in a waggon which led the caravan, was so
constructed that the arm and hand moved with perfect freedom, the
magnetic needle being attached to it; the hand, however, pointed to the
south, the negative end being fixed in it. The Chinese also used a
needle which was freely suspended in the air, attach