[25] Page 5, line 28. Page 5, line 35. Jacobus Severtius.—Jacques Severt, whose work, De Orbis Catoptrici sev mapparvm mvndi principiis descriptione ac usu libri tres (Paris, 1598), would have probably lapsed into obscurity, but being just newly publisht was mentioned by Gilbert for its follies.
[26] Page 5, line 30. Page 5, line 38. Robertus Norman.—Author of the rare volume The Newe Attractiue, publisht in London, 1581, and several times reprinted. This work contains an account of Norman's discovery of the Dip of the magnetic needle, and of his investigation of it by means of the Dipping-needle, which he invented. He was a compassmaker of the port of London, and lived at Limehouse.
[27] Page 5, line 32. Page 5, line 40. Franciscus Maurolycus.—The work to which the myth of the magnetic mountains is thus credited is, D. Francisci Abbatis Messanensis Opuscula Mathematica, etc. (Venet, MDLXXV, p. 122a). "Sed cur sagitta, vel obelus à vero Septentrione, quandoque ad dextram,
quandoque ad sinistram declinat? An quia sagitta, sicut magnes (cuius est simia) non verum Septentrionem, sed insulam quandam (quam Olaus Magnus Gothus in sua geographia vocat insulam magnetum) semper ex natura inspicere cogitur?"
[28] Page 5, line 35. Page 5, line 43. Olaus Magnus.—The famous Archbishop of Upsala, who wrote the history of the northern nations (Historia de Gentibus Septentrionalibus), of which the best edition, illustrated with many woodcuts, appeared in Rome in 1555. An English edition entitled A Compendious History of the Goths, Swedes, and Vandals, and Other Northern Nations was printed in London in 1658; but it is much abbreviated and has none of the quaint woodcuts. The reference on p. 5 appears to be to the following passage on p. 409 (ed. 1555). "Demum in suppolaribus insulis magnetum montes reperiuntur, quorum fragmentis ligna fagina certo tempore applicata, in saxeam duritiem, et vim attractivam convertuntur," or the following on p. 89: "Magnetes enim in extremo Septentrionis veluti montes, unde nautica directio constat, reperiuntur: quorum etiam magnetum tam vehemens est operatio, ut certis lignis fagineis conjuncti, ea vertunt in sui duritiem, & naturam attractivam." On p. 343 is a woodcut depicting the penalties inflicted by the naval laws upon any one who should maliciously tamper with the compass or the loadstone, "qui malitiosè nauticum gnomonem, aut compassum, & præcipuè portionem magnetis, unde omnium directio dependet, falsaverit." He was to be pinned to the mast by a dagger thrust through his hand. It will be noted that the ships carried both a compass, and a piece of loadstone wherewith to stroke the needle.
There is in the Basel edition of this work, 1567, a note ad lectorem, on the margin of Carta 16a, as follows:
"Insula 30 milliarium in longitud. & latitud. Polo arctico subjecta.
"Vltra quam directorium nauticum bossolo dicũ uires amittit: propterea quòd ilia insula plena est magnetum."
This myth of the magnetic mountains, probably originating with Nicander, appears, possibly from an independent source, in the East, in China, and in the tales of the Arabian Nights.
Ptolemy gives the following account in his Geographia (lib. vii., cap. 2):