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13th century according acquainted anno appear arcs of 180 artificial magnet Atlantic Ocean attraction Azores bar of prepared Bible Guiot cafe called Canton Cape CHAPTER clination distance of 90 diurnal dividing the surface earth eastward equator ESSAY on MAGNETISM globe greatest equatorial declination Halleyan lines ingenious iron or steel latitude latter end likewise lines of declination lines of east little needle longitude magnetic and true magnetic declination magnetic needle mariner's compass mentioned misphere motion moved from west natural magnets needle is moved netic poles north end north pole northern hemisphere observations opposite meridian opposite parallels Pacific Ocean Petrus Peregrinus Plate poles are situated poles thereof poles were situated prepared iron ridian Sect Senebier situated in opposite south end south magnetic pole south pole southern hemi sphere sun's heat tion Treatise on Magnetism true and magnetic true poles west declination west to east west variation followed
Page xi - Then they look for the right point, And when they have touched a needle (on it) And fixed it on a bit of straw, Lengthwise in the middle, without more, And the straw keeps it above ; Then the point turns just Against the star undoubtedly.
Page xi - C'est uns ars qui ne puet mentir. TRANSLATION. This same star does not move, and They (the mariners) have an art which cannot deceive, By the virtue of the magnet, An ugly brownish stone, To which iron adheres of its own accord. Then they look for the right point, And when they have touched a needle (on...
Page vi - Plutarch, it seems to appear that the Egyptians were not ignorant of it. Pythagoras, Ptolemy, Hippocrates, Empedocles, Democritus, Leucippus, Epicurus, and many more of the ancients, knew and admired this wonderful property of the magnet. It was on account of this quality that Thales and Anaxagoras gave it a soul ; and Plato, who called it the stone of Hercules, said that the cause of its attraction was divine.
Page 32 - Canton's doctrine, they would not have long continued fo; for from the intenfe heat of the fun in the torrid zone, according to the principles already explained, the north pole muft have foon retired to the north-eaftward, and the fouth pole to the fouth-eaftward.
Page 27 - ... in the night, or by the next morning. The diurnal variation is irregular when the needle moves flowly eaftward in the latter part of the morning, or weftward in the latter part of the afternoon ; alfo when it moves much either way after night, or fuddenly both ways in a mort time.
Page 1 - Now, as the north pole of one magnet repels the north pole of another magnet...
Page 33 - And, according to the opinions of the moft ingenious authors on this fubjeft, it is generally allowed, that at this time the north magnetic pole is considerably nearer to the north pole of the earth, than the fouth magnetic pole is to the fouth pole of the earth.
Page xii - Goropius's pretence, that the compafs muft be the invention of the Danes, Dutch, or Germans,, becaufe the thirty-two points on it are written, and pronounced in the Dutch or Teutonic language, has no better grounds than the EnglHh claim from the words Corapafs and Box t.
Page xi - Then the point turns just Against the star undoubtedly. " When the night is dark and gloomy, That you can see neither star nor moon, Then they bring a light to the needle...
Page x - Icelle eftoile ne fe muet, Une arts font qui mentir ne puet, Par la virtu de la manete* Une piere laide et brunete, Ou il fers volenters fe-joint. . 5: Ont regardent lor + droit point Puez c' une aguile lont touchie, Et en un feftu lont fifhie En longue J la mette fens plus,.