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aptista Porta the Neapolitan, who wrote forty years before Gilbert, discredited the legend. "_Flavius_ saith, an Italian found it out first, whose name was _Amalphus_, born in our {57} Campania. But he knew not the Mariners Card, but stuck the needle in a reed, or a piece of wood, cross over; and he put the needles into a vessel full of water that they might flote freely." (Porta's _Natural Magick_, English translation, London, 1658, p. 206.) See also Lipenius (_op. citat._ p. 390). The pivotting of the needle is expressly described in the famous _Epistle_ on the Magnet of Peter Peregrinus, which was written in 1269. Gasser's edition, _Epistola Petri Peregrini ... de magnete_, was printed in Augsburg in 1558. In Part II., cap. 2, of this letter, a form of instrument is described for directing one's course to towns and islands, and any places in fact on land or sea. This instrument consists of a vessel like a turned box (or _pyxis_) of wood, brass, or any solid material, not deep, but sufficiently wide, provided with a cover of glass or crystal. In its middle is arranged a slender axis of brass or silver, pivotted at its two ends into the top and the bottom of the box. This axis is pierced orthogonally with two holes, through one of which is passed the steel needle, while through the other is fixed square across the needle another stylus of silver or brass. The glass cover was to be marked with two cross lines north-south and east-west; and each quadrant was to be divided into ninety degrees. This the earliest described pivotted compass was therefore of the cross-needle type, a form claimed as a new invention by Barlowe in 1597. The first suggestion of suspending a magnetic needle by a thread appears to be in the _Speculum Lapidum_ of Camillus Leonardus (Venet., 1502, fig. k ij, lines 25-31): "Na tacto ferro ex una [=p]te magnetis ex opposita eius [=p]te appropinquato fugat: ut ex[=p]i[~e]tia docet de acu appenso filo." The earliest known examples of the "wind-rose" are those in certain parchment charts preserved in the Biblioteca Marciana in Venice. These go back to 1426 or 1436, the best being ascribed to Andrea Bianco. They have the North indicated by a fleur-de-lys, a trident, a simple triangle, or a letter T; while the East is distinguisht by a cross. The West is marked with a P. (see Fincati, _op. citat._). The eight marks in order, clock wise, run thus, [Lily] (or T). G. [Cross] (or L) S. O. A (or L
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