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.] "I heard it said that the captains in the Indian seas substitute for the needle and reed a hollow iron fish, magnetized, so that, when placed in the water, it points to the north with its head and to the south with its tail. The reason that the fish swims, not sinks, is that metallic bodies, even the heaviest, float when hollow, and when they displace a quantity of water greater than their own weight." It may fairly be inferred, from this passage, that, at the time spoken of, (1240,) the practice was already of long standing in this quarter, and that the needle and its polarity had been long known and employed at sea. That is, the Arabs had become familiar with the loadstone in 1240, while Friar Bacon regarded it, in England, as a huge curiosity in 1260,--twenty years afterwards. The priority of the invention would seem to be thus incontestably proven for the Arabs. But we shall see speedily that it derived its origin from a region situated still farther to the east, and many centuries earlier.