A famous Chinese dictionary, terminated in the year 121 of our era, thus defines the word magnet:--"The name of a stone which gives direction to a needle." This is quoted in numerous modern dictionaries. One published during the Tsin dynasty--that is, between 265 and 419--states that ships guided their course _to the south_ by means of the magnet. The Chinese word for magnet--_Tchi nan_--signifies, Indicator of the South. It was natural for the Chinese, when they first saw a needle point both north and south, to take the Antarctic pole for the principal point of attraction, for with them the south had always been the first of the cardinal points,--the emperor's throne and all the Government edifices invariably being built to face the south. A Chinese work of authority, composed about the year 1000, contains this passage:--"Fortune-tellers rub the point of a needle with a loadstone to give it the power of indicating the south." A medical natural history, published in China in 1112, speaks even of the variation of the needle,--a phenomenon first noticed in Europe by Christopher Columbus in 1492:--"When," it says, "a point of iron is touched by a loadstone, it receives the power of indicating the south: still, it declines towards the east, and does not point exactly to the south." This observation, made at the beginning of the twelfth century, was confirmed by magnetic experiments made at Pekin, in 1780, by a Frenchman; only the latter, finding the variation to be from the north, set it down as from 2° to 2° 30' to the west, while the Chinese, persisting in calling it a variation from the south, set it down as being from 2° to 2° 30' to the east. Thus, the Chinese, who were acquainted with the polarity of a magnetized needle as early as the year 121, and who noticed the variation in 1112, may be safely supposed to have employed it at sea in the long voyages which they made in the seventh and eighth centuries, the route of which has come down to us. Their vessels sailed from Canton, through the Straits of Malacca, to the Malabar coast, to the mouths of the Indus and the Euphrates. It is difficult to believe that, aware of the use to which the needle might be applied, they did not so apply it.