It is now generally understood that magnetic cars, "based on the same principle as the compass," were used in China much earlier than this. The Helleno-Roman world of antiquity, in describing the magnet, only dwelt on its attraction for iron, and did not notice its power of indicating the poles; whereas the Celestials were aware in the first place of the communication of magnetic fluid to iron, and in the second place of the mysterious power of iron so magnetized, as early as about A.D. 120. The earliest use of the water-compass in China is fixed by Klaproth at A.D. 1111-17; and as to the magnetic figures or magnetic cars with which in earlier times Chinese junks sailed to the south of Asia, and Chinese travellers made their way across the plains and mountains to the west of their country, it must not be assumed that their use was universal. Thus, in the fifth century A.D., when Wu-Ti, afterwards Emperor, stormed Singanfu (417 A.D.), he seized upon one of these as a great curiosity. It is uncertain, as already remarked, when the complete compass, or even the polarity of the magnet, was first discovered in Europe. We may, however, note the following evidence: (1) Alexander Neckam, an English monk of St. Albans (born 1157, died 1217), who had studied for some time in the University of Paris, refers more than once to what we may suppose was a compass needle, placed on a metal point.[286] This, he implies, was then in common use among sailors, and was not merely a secret of the learned. For, "when the mariners cannot see the sun clearly in murky weather or at night, and cannot tell which way their prow is tending, they put a needle above a magnet, which revolves until its point looks North and then stands still." These words were probably written between 1190-1200. [Footnote 286: Cf. Neckam's references. (α) In his work, _De Utensilibus_: "Qui ergo munitam vult habere navem ... habeat etiam acum jaculo superpositam: rotabitur enim et circumvolvetur, donec cuspis acus respiciat Septentrionem, sicque comprehendent quo tendere debeant nautae, cum Cynosura latet in aeris turbatione, quamvis ea occasum nunquam teneat propter circuli brevitatem." (β) In his _De Naturis Rerum_, c. 98: "Nautae ... mare legentes, cum beneficium claritatis solis in tempore nubilo non sentiunt, aut ... cum caligine ... tenebrarum mundus obvolvitur, acum super magnetem ponunt, quae circulariter circumvolvitur usque dum ejus motu cessante, cuspis ipsius Septentrionalem Plagam respiciat."]