=A.D. 121.=--The Chinese knew of old the magnet, its attractive force and its polarity, but the most ancient record made of the peculiar property possessed by the loadstone of communicating polarity to iron is explicitly mentioned in the celebrated dictionary “Choue-Wen,” which Hin-tchin completed in A.D. 121, the fifteenth year of the reign of the Emperor Ngan-ti of the Han dynasty. This dictionary contains a description of the manner in which the property of pointing with one end toward the south may be imparted to an iron rod by a series of methodical blows, and alludes to (“Tseu”) the “stone with which a direction can be given to the needle.” “In Europe it has been thought that the needle had its chief tendency to the north pole; but in China the south alone is considered as containing the attractive power” (Sir G. Staunton, “Account of an Embassy,” London, 1797, Vol. I. p. 445). Le Père Gaubil, who was sent to China in 1721 and died in Pekin 1759, says (“Histoire ... de la dynastie de Tang,” in “Mémoires concernant ...” Vol. XV) that he found, in a work written towards the end of the Han dynasty, the use of the compass distinctly marked to distinguish the north and the south. He also states, though doubtless erroneously, that that form was given it under the reign of Hian-Tsoung. With reference to the magnetic attraction to the pole, it is well to bear in mind that no allusion whatsoever is made thereto by any of the writers of classical antiquity. This much has already been stated under date B.C. 1000–907. It certainly appears to have escaped the attention of the ancient Greeks and Romans, whose admiration, according to the learned French physician Falconet (“Dissert. Hist. et Crit.”), was excited solely by the attractive property of the loadstone. The Rev. Father Joseph de Acosta (“Natural and Moral History of the Indies,” translation of C. R. Markham, lib. i. cap. 16) thus alludes to the above subject: “I finde not that, in ancient bookes, there is any mention made of the vse of the Iman or Loadstone, nor of the Compasse (_aguja de marear_) to saile by; I beleeve they had no knowledge thereof.... Plinie speakes nothing of that vertue it hath, alwaies to turne yron which it toucheth towards the north.... Aristotle, Theophrastus, Dioscorides, Lucretius, Saint Augustine, nor any other writers or Naturall Philosophers that I have seene, make any mention thereof, although they treat of the loadstone.” Thomas Creech, in the notes to his translation of Lucretius’ “De Natura” says: “Nor indeed, do any of the ancients treat of this last (the directive) power of the loadstone ... and Guido Pancirollus justly places it among the modern inventions.”