The ancients were fully acquainted with the loadstone, and with its power of attracting iron, though they were totally ignorant of its polarity. That they were so, is evident from the fact that the classic authors and ancient works upon navigation and kindred subjects do not furnish one word upon the subject. Claudian has left, in one of his idyls, a long description of the stone, and of its peculiar, indeed, magical, affinity for iron. Had he entertained the most distant idea that this stone could communicate to a steel needle the power of indicating the north, it is not to be supposed for an instant that he would have omitted mentioning it. The earliest name of the loadstone was Hercules' Stone, which was soon changed to magnes, from the fact that it was found in abundance in a region called Magnesia, in Lydia. Hence our word magnet. It was not till the fourth century of our era that the quality of repelling as well as of attracting iron seems to have been discovered. Marcellus, the physician of Theodosius the Great, is the first author who mentions this new quality.
The Romans, who acquired a knowledge of the magnet from the Greeks, preserved the name, though several of their authors, and Pliny among them, mention a tradition, that the magnet was so called from a shepherd named Magnes, who was the first to discover a mine of loadstone, by the nails in his shoes clinging to the metal.
The first mention in European history of the polarity of the magnetized needle, and of its importance to mariners, occurs in a satirical French poem written in 1190 by one Guyot de Provins. His object was to level, by implication, an invective against the Court of Rome; and he did it in the following neat manner. The translator has endeavored to preserve the quaint style of the original:
"As for our Father the Pope,
I would he were like the star
Which moves not. Very well see it
The sailors who are on the watch.
By this star they go and come,
And hold their course and their way.
They call it the Polar Star.
It is fixed, very unchangeable:
All the others move,
And alter their places and turn,
But this star moves not.
They make a contrivance which cannot lie,
By the virtue of the magnet.
An ugly and brownish stone,
To which iron spontaneously joins itself,
They have: and they observe the right point,
After they have caused a needle to touch it,
And placed it in a rush:
They put it in the water, without any thing more,
And the rush keeps it on the surface;
Then it turns its point direct
Towards the star with such certainty,
That no man will ever have any doubt of it;
Nor will it ever for any thing go false.
When the sea is dark and hazy,
That they can neither see star nor moon,
Then they place a light by the needle,
And so they have no fear of going wrong:
Towards the star goes the point,
Whereby the mariners have the skill
To keep the right way.
It is an art which cannot fail."
It may be very properly inferred, from the fact that the poet does not merely allude to the compass, but describes it and the polar star at some length, that it was not generally known, and, in fact, had been lately introduced into the Mediterranean. Whence it had been introduced there, we shall learn as we proceed.
The second historical mention of the compass occurs in a description of Palestine by Cardinal Jacques de Vitry, in the year 1218, in which is the following passage:—"The loadstone is found in India, to which, from some hidden cause, iron spontaneously attaches itself. The moment an iron needle is touched by this stone, it at once points towards the North Star, which, though the other stars revolve, is fixed as if it were the axis of the firmament: from whence it has become necessary to those who navigate the seas."
Brunetto Latini, a grammarian of Florence, and preceptor of Dante, settled in Paris about the year 1260, and composed a work entitled the "Treasure," in which he distinctly describes the process and the consequence of magnetizing a needle. He also went to England, and, in a letter of which fragments have been published, writes thus:—"Friar Bacon showed me a magnet, an ugly and black stone, to which iron doth willingly cling: you rub a needle upon it, the which needle, being placed upon a point, remains suspended and turns against the Star, even though the night be stormy and neither star nor moon be seen; and thus the mariner is guided on his way."
The Italian Jesuit Riccioli, in his work upon Geography and Hydrography, states, that before 1270, the French mariners used "a magnetized needle, which they kept floating in a small vessel of water, supported on two tubes, so as not to sink."
All these authors agree in fixing the period at which the use of the needle was popularized in Europe, at the latter part of the twelfth and the commencement of the thirteenth century. Not one of them mentions the inventor by name, or even indicates his nation. This circumstance leads to the conviction that it was unknown to them, and that, consequently, the inventor was not a European. The theory that the Europeans obtained it from the Arabians, and the Arabians from the Chinese, is supported by the following facts:
A manuscript work, written by an Arabian named Bailak, a native of Kibdjak, and entitled "The Merchant's Guide in the Purchase of Stones," thus speaks of the loadstone in the year 1242:—"Among the properties of the magnet, it is to be noticed that the captains who sail in the Syrian waters, when the night is dark, take a vessel of water, upon which they place a needle buried in the pith of a reed, and which thus floats upon the water. Then they take a loadstone as big as the palm of the hand, or even smaller. They hold it near the surface of the water, giving it a rotary motion until the needle turns upon the water: they then withdraw the stone suddenly, when the needle, with its two ends, points to the north and south. I saw this with my own eyes, on my voyage from Tripoli, in Syria, to Alexandria, in the year 640. [640 of the Hegira, 1240 A.D.]