On the Magnet/Index

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774450On the Magnet — IndexWilliam Gilbert (1544–1603)

INDEX.

Abano, Pietro di (Apponensis or Apianus), 2.
Abbas, Hali ('Alí ibn Al 'Abbās, Al Majúsi, 2, 6.
Abohalis, 47. See also Avicenna.
aciarium or acies, also aciare, 18, 23, 33, 36.
Acosta, Josephus, 5.
adamant, 11.
æquator, the magnetick, 13, 79.
Aetius Amidenus, 2.
Affaytatus, Fortunius, 6.
agate, non electrick, 51, 53.
Agricola, Georgius, 2, 3, 10, 19, 26, 111, 112.
Agrippa, H. Cornelius, 3.
aimant, 11.
Albategnius (Muhammad ibn Jābir, Al-Battāni, 237.
Albertus Magnus, 2, 7, 18, 111.
Alexander Aphrodiseus, 3, 48, 92.
Alexandria, Hero of, 58.
Alfonso, Diego, 178.
Alfonsus the Wise (Alphonsus X.), 237.
Amalfians said to have first constructed the compass, 4.
Amatus Lusitanus, 2.
amber, 47, 49-60, 85, 112, 116.
amethyst, electrical properties of, 48.
amianth, 11.
Amidenus, Aetius, 2.
amphitane, 111.
Anatolismus, or Northeasting, 167.
Anaxagoras, 61, 208.
Andrea Doria (Admiral), 4.
Antonius de Fantis, 107.
Antonius Musa Brasavolus, 2.
Antony, the denarius of, 110.
Apianus. See Abano.
Apponensis. See Abano.
Aquinas, Thomas, 3, 64.
Aractensis, Mahometes, 234, 237.
Archelaus, 208.
Ardoynis, Santes de, 2.
Arias Montanus, 4.
Aristarchus, 214, 237.
Aristotle:

De Anima, 1, 11, 61, 210.
De Cœlo, 226, 232.
De Mirabilibus Auscultationibus, 22.
Meteorologica, 35, 39.
on material of the metals, 19, 20.
on the element of earth, 43.
on motions, 45, 219, 225.
on primary form, 65.
on the Primum Mobile, 220.
on animate nature of planets, 208.

armature, 87.

armed loadstones, 86, 87, 88, 89.
Arnaldus de Villa nova, 2, 7.
Arsinoe, Temple of, 2.
Attraction, 46, 60, 64, 68, 90, 98, 109.
Avicenna (Abu 'Ali Husain ibn 'Abd Allah, Ibn Síná; also called Abohalis):

writes on the magnet, 2.
on falling masses of iron, 26.
alleges loadstone an antidote to iron poison, 35.
on the property of attraction, 49.

Augsburgers (Augustani), the, prescribe loadstone in plaster, 33.

axis, the magnetick, 13, 81, 212.
Azores, variation of compass at the, 4, 154, 156, 167.

Bacon, Roger, 5.
Bambola, or Bilbilis, 23.
Baptista Montanus, 2.
Baptista Porta. See Porta.
Barbarus, Hermolaus, 3.
Barlowe, William (Rev. Archdeacon), his book, The Navigators Supply, 8.
basil leaves alleged not to be attracted, 48.
belemnites are electrical, 48.
Bencora (Thābit ibn Kurrah, Al Harrani; also called Thebitius), 117, 236.
Benedictus, Joannes Baptista (Giambattista Benedetti), 167.
beryl, electrick properties of, 48.
Bessardus (Toussaincte de Bessard), 5, 116, 153.
Blondus, Flavius, the historian, 4.
Borough, William, his book on the Variation of the Compass, 8.
Borrholybicum (North-north-west), 160.
Brahe, Tycho, 174, 229.
Brandoe, the island of, 181.
Brasavolus, Antonius Musa, 2.
Bristolla, or Bristol gem, 48.
burnt clay, magnetick properties of, 26, 43.

Cabot, Sebastian, 4.
Cælius Calcagninus, 7.
Cæsare, or Cesare, Giulio, 141.
Calaber, Hannibal Rosetius, 3,
calamita or kalamita, 11.
Calcagninus, Cælius, 7.
Camillus Leonhardus, 3.
Candish, or Cavendish, Thomas, *iij, 117.
cap of iron for a loadstone, 86, 89, 90, 95.
carabe, or karabe, 47.
carbuncle, electrick properties of, 48, 111.
Cardan, Hieronymo, 2.

De Proportionibus:
on iron and earth, 43, 62, 67.
on distance of centre of cosmos, 169.
De Rerum Varietate:
on fall of meteorick iron, 26.
on attraction of amber, 49.
on a perpetual motion engine, 107.
De Subtilitate:
alleges magnet to feed on iron, 37, 63, 92.
on magnet that draws silver, 110.
on magnetick influence of star in tail of Ursa Minor, 5, 116, 153.

carnelian, the, 51, 55.

catoblepas, the antelope called, 63.
Cesare, Giulio, 141.
chalybs, 18, 25, 33.
chatochitis, 111.
chemists, the, 19, 20, 21, 24, 37, 66.
China, 4, 8, 9, 11, 17, 32, 119.
Chinocrates, 2.
circumpulsion, doctrine of, 3, 61.
clamps (open kilns), 26.
clay when burnt is magnetick, 26, 43, 97.
clepsydra, 231.
Coimbra, College of, 5.
coition (mutual attraction), 45, 46, 60, 65, 67, 68, 81, 98, 99, 103, 109, 131.

definition of, *vj, 68.
orbe of, *vj.

colours of loadstones, 9, 10, 27.

Como, 23.
compass, alleged invention of, by Amalfians, 4.

origin of the compass-card, 4, 165.
the mariners' (pyxis), 3, 115, 147, 165, 172.
the little (pyxidula), 181, 202.
different forms of, Italian, Baltic, Portuguese, English, 165, 166, 177, 181.

conduction, magnetick, 85, 104, 125.

consequent poles, 129, 142.
Copernican system, 231.
Copernicus, Nicolas, 212, 214, 216, 231, 237, 238, 240.
Cordus, Valerius, 10.
Cornelius Agrippa, 3.
Cornelius Gemma, 63.
Cornelius Tacitus, 25.
corolla intorta, or contorted circlet, 238, 240.
Cortes, Martin, 5, 116, 152.
Corvo, Island of, 167.
Costa, Filippo (of Mantua), 141.
Costæus, Joannes, 3, 62, 227, 228.
creagus, the, or flesh-magnet, 110.
crystal, rock, 48, 52, 59, 111
Curtius, Nicolaus, 35.
Cusan (Michael Khrypffs), Cardinal de Cusa, 3, 64, 108.
Cynosure, the, or Pole-star, 14, 81, 117, 222, 235.

Dean, Forest of, loadstone found in the, 11.
decay of the magnetick virtue, 18, 37, 124, 138, 149.
declination, the, or dip, 184.
denarius of Antony, 110.
diamond, an electrick, 48, 50, 59, 111.

alleged power to attract iron, 109, 112.
alleged antipathy to magnet, 2, 7, 109, 143.
experiments upon, 143.

Diego Alfonso, 178.

Differences between electricks and magneticks, 47, 60, 65.
Dioscorides, 1, 2, 9, 32.
dip, the, also called declination, 8, 46, 184-204.
dipping-needle, or declination instrument, 185, 203.
direction, or directive force, 41, 46, 115, 119.
dividing a loadstone, 16, 72, 100, 121, 122, 127, 130, 136, 145, 146.
Dominicus Maria Ferrariensis, 212, 213.
Doria, Andrea (Admiral), 4.
Drake, Sir Francis, *iij bis, 117.
Du Puys (also called Puteanus), 3, 63.

Earth, the, a great magnet, 38, 39, 40, 41, 44, 119, 211.
echeneis (the sucking fish), 7, 63, 110.
Ecphantus, 214.
effluvia, electrical, 52, 53, 59, 66.
magnetical, 61.
electrical attraction, 50, 51, 111.
electrick force, definition of, 52.
electricks, *vj, 46-60.
electrum (ἤλεκτρον), 47.
emerald is non-electrick, 51.
emery, 22, 51.
Empedocles, 208.
Encelius (or Entzelt, Christoph.), 3, 111.
Epicurius, 61, 62.
Erasmus Rheinholdus, 213.
Erastus, Thomas, 3, 22.
errors in navigation, 166, 177.
Evax, King of Arabia, 111.
Euripides, 9, 11, 18.

Fallopius, Gabriellus, 3, 34, 35, 112.
Fantis, Antonius de, 107.
Fernelius, Joannes Franciscus, 4.
Ficinus, Marsilius (or Marsiglio Ficino), 3, 7, 116 153.
filings of iron, 37, 69, 90, 91, 92, 104.
Filippo Costa. See Costa.
fire destroys magnetick properties, 66, 67, 91, 124.
flame destroys electrification, 59.
flame hinders not magnetick attractions, 66.
Flavius Blondus. See Blondus.
flies in amber, 47.
form versus matter, 52, 65.
Fra Paolo, 6.
Fracastorio, Hieronymo, 5, 50, 67, 71, 91, 110, 113, 152.
Franciscus Maurolycus. See Maurolycus.
Franciscus Rueus. See Rueus.

Gagates. See jet.
Galen, 2, 9, 32, 35, 39, 46, 49, 61, 62, 63.
Gallus, Marbodæus, 2, 7.
garlick, its reputed antagonism to magnetism, 2, 32, 64.
Gartias ab Horto, 32.
Gaudentius Merula, 7.
Gauricus, Lucas, 7.
Geber (Jābir ibn Háiyán, Al-Tarsusī) 21.
Gemma, Cornelius, 63.
gems, electrick properties of, 48, 51.
geniter, 47.
Georgius Agricola. See Agricola.
Gilbert, Adrian, 11.
Gilgil Mauritanus, 19.
Gioia, or Goia, of Amalfi, 4.
Giulio Cæsare, 141.
glass, an electrick by friction, 48, 54, 59.
use of loadstone in making, 111.
goat's blood, 7.
Gonzalus Oviedus, 4.
Goropius, Henricus Becanus, 4.
Grotius, Hugo, 167, 168.

Haematite, 22, 51.
Hali Abbas ('Ali ibn Al 'Abbás, Al Masúfí), 2, 6.
Hannibal Rosetius Calaber, 3.
Hariot, Thomas, 7.
Heat, effect of on loadstone, 66, 67, 93, 123, 124.
Helmshuda, 167.
Heraclea, the city of, 8.
Heraclean stone, or stone of Hercules, 8, 43, 61, 169.
Heraclides, 214.
Heraclitus, 208.
Hermes, 209.
Hermolaus Barbarus, 3.
Hero of Alexandria, 58.
Hipparchus, 213, 214, 234, 235, 237.
Hippocrates, 8, 35, 51, 61.
horizon, the magnetick, defined, 80.
Horto, Gartias ab, 32.
Horus, the bone of, or Os Ori, 9.
hot iron not magnetick, 66.
Hues, Robert, 7.
Hugo Grotius, 167, 168.

Inclination. See dip.
interposition of bodies, 53, 66, 83, 85, 89, 137.
iris gem, the, 48.
iron, its nature and occurrence, 19, 20, 22, 25.

filings of, 37, 69, 90, 91, 92, 104.
its various names and qualities, 23, 33, 36.
its various uses, 23, 24, 39, 86, 90, 95.
medical uses of, 33, 35.
surpasses loadstone, 69, 95.
verticity in, 85, 123, 139.

iron ore is magnetick, 18, 27, 38, 43.

has poles, 28.
islands, magnetick influence of, 5, 153, 161.

Jacobus Severtius, 5.
jet, 47, 48, 53, 55, 86.
Joannes Baptista Porta. See Porta.
Joannes Baptista Montanus, 2.
Joannes Costæus. See Costæus.
Joannes Franciscus Offusius, 46.
Joannes Goia. See Gioia.
Joannes Langius, 3.
Joannes Taisner, or Taisnier. See Taisnier.
Jofrancus Offusius, 46.
Josephus Acosta, 5.
Julius Cæsar Moderatus, 141.
Julius Cæsar Scaliger. See Scaliger.

Kendall, Abraham, 7, 178.
Korrah, Thebitius Ben. See Bencora.

Lactantius, Lucius, 219.
Lagos, Rodriguez de, 177.
Langius, Joannes, 3.
lapis magnetis, 8.
lapis specularis, muscovy stone, or mica, 11, 48, 52.
latitude in relation to dip, 196, 200.
Leonardus (or Leonhardus), Camillus, 3.
Levinus Lemnius, 3.

lifting power of loadstones, 86, 89, 97.
lily of the compass, 117, 152, 165, 177.
liquids, electrical attraction of, 55.
attraction on surface of, 57.
Livio Sanuto, 5, 153, 167.
loadstone armed and unarmed, 86, 87, 88.

as medicine, 32.
in plasters, 33.
rock, the, 5, 6, 18, 116, 152.
various names of, 11.
colours of, 9, 10, 27.
various sources of, 8, 25, 32.

London, magnetick variation at, 154, 163.

longitude, magnetick finding at, 166.
long magnets, advantage of, 82, 83, 99, 101
Lucania, fall of meteorick stones in, 26.
Lucas Gauricus, 7.
Lucretius, 2, 3, 8, 49, 61.
Lusitanus, Amatus, 2.
Lynschoten, Hugo van, *iiij.

Magnes, μάγνης, μαγνῆτις, 11.
Magnesia, 8.
Magnetick axis of terrella, 81, 212.

axis of earth, 13, 81, 212.
horizon, 80.
meridian, 79, 152.
mountains or rocks, 5, 6, 18, 116, 152.
islands, 5, 153, 161.
motions, the five, 45.

Magnus, Albertus. See Albertus.

Magnus, Olaus, 5, 6.
Mahometes Aractensis, 234, 237.
Mahomet's tomb, 2.
Manardus, Joannes, 35.
Marbodæus Gallus, 2, 7.
Marcellus Empiricus, 2.
Marco Polo (Paulus Venetus), 4.
mariners' compass. See compass.
Mars, saffron of (Crocus Martis), 34, 91.
Marsiglio Ficino. See Ficinus.
Martin Cortes, 5, 116, 152.
matter and form, 52, 65.
Matthæus Silvaticus, 3.
Matthiolus, Petrus, 2, 3.
Mauritanus, Gilgil, 19.
Mauritanus, Serapio, 2, 6.
Maurolycus, Franciscus, 5, 42, 153, 180.
medicinal use of iron, 33.
of loadstone, 32.
Medina, Pedro de, 166.
Menelaus, 234, 237.
meridian, magnetick, 79, 152, 163.
Merula, Gaudentius, 7.
meteorick stones, falls of, 26, 27.
mica (or muscovy stone), 11, 48, 52.
μικρόγη. See terrella.
moisture stops electrick action, 53, 56.
Montagnana, B., 35.
Montanus, Arias, 4.
Montanus, Joannes Baptista, 2.
Moors, Serapio and the, 6.
mountains, magnetick, 5, 6, 18, 116, 152.
movement of trepidation, 117.
Musa Brasavolus, Antonius, 2.
muscovy stone, 11, 48, 52. See also mica.
myths of the magnet, 2, 3, 5, 6, 7, 18, 32, 63, 107, 109, 110, 111, 116, 143, 153, 228
motions, the various magnetical, 46.

Names of amber, 47.
names of the loadstone, 11.
names given to the magnetick poles, 15, 115, 125, 129.
Nicander of Colophon, 8, 9.
Nicetas, 214.
Nicolas Copernicus, 212, 214, 216, 231, 237, 238, 240
Nicolaus Myrepsus, or Præpositas, 33.
non-electrick bodies, 51, 55.
Nonius, Petrus (Pedro Nuñez), 166.
Norman, Robert, 5, 8, 153, 161, 162.

supposes a point respective, 5, 153, 161, 162.
his Newe Attractive, 8.
discoverer of the dip, 8.

Norumbega, the city of, 154.

Nova Zembla, 152, 179.

Offusius, Jofrancus, 46.
Olaus Magnus, 5, 6.
opal becomes electrical, 48.
orbe of virtue, 76, 96, 191, 205
orbes of planets, 208, 215.
Oribasius, 2.
Orpheus, 11, 61, 209.
Oviedus, Gonzalus (Gonzalo Fernandez de Oviedo y Valdès), 4.

Pantarbes, 111.
Paolo (Paulus Æginæ), 35.
Paolo, Rev. Maestro (Fra Paolo Sarpi), 6
Paolo the Venetian (Marco Polo), 4.
Paracelsus (Bombast von Hohenheim).

asserts the stars to attract iron, 3.
his emplastrum of loadstone, 33.
his method of strengthening loadstones, 93.

Parmenides, 208.

pearls are not electrick, 51, 55.
Pedro de Medina, 166.
percussion excites verticity, 139.
Peregrinus, Peter,

his book, 5.
on cause of magnetick direction, 5, 116, 153.
on perpetual motion engine, 107.
affirms a terrella to revolve daily, 223.

Peripateticks, the, 20, 41, 43, 45, 65, 218, 222, 225, 227, 228.
perpetual motion machine, 107.
Peter Peregrinus. See Peregrinus.
Peter Plancius. See Plancius.
Petrus Apponensis. See Abano, Pietro di.
Petrus Nonius. See Nonius or Nuñez.
Philolaus, 214.
Philostratus, 111.
Pictorio, G., 6, 49.
piedramant, 11.
Plancius, Peter, *v bis.
planets, influence of, 20, 137, 142.
plasters, magnetick, 32, 33.
Plato, 3.

in the Io, discusses name and properties of the magnet, 1, 9, 11, 18.
in the Timæus, suggests the theory of circumpulsion, 61.
his Atlantis, 159.
on life in the universe, 208.

Pliny (C. Plinius Secundus).

on loadstone fables, 1, 2, 9, 18.
his mistake about Æthiopian loadstones, 17.
on the five kinds of loadstones, 9.
on the alleged discovery of the loadstones, 8.
on the alleged magnetick mountains, 18.
on a locality where loadstone was found, 11.
on the occurrence of iron in Spain, 25.
on the Sagda and the Catochites, 111.
on the silver denarius of Antony, 110.
on the use of loadstone by glass-makers, 111.
on the shadow of a gnomon of a sun-dial at Rome, 213.

Plotinus, 218.

Plutarch, Claudius.

on the garlick fable, 32.
says something flammable exists in amber, 54.
his theory of circumpulsion, 3, 62.

polarity. See verticity.

pole, the, elevation of, 200, 213.
poles, magnetick, of a loadstone, 13, 41, 72, 81, 144.
poles are not points, 12, 41, 72, 96.
Polo, Marco, 4.
Porta, Joannes Baptista (Giambattista della Porta).

his narration of marvels, 6.
on various tempering of iron, 24.
asserts loadstone a mixture of stone and iron, 63.
on his assertion that loadstones have hairs, 66.
asserts vapour to be cause of attraction, 67.
his error as to change of verticity, 73.
suspends iron upwards by a thread, 92.
his error as to centre of the orbe of virtue, 95.
his error as to the polarity which causes repulsion, 102.
his error as to magnetick opposing forces, 103.
experiment with a balance, 108.
his error as to iron being intoxicated, 138.
his error as to iron excited by a diamond, 143.
his error as to the pointing of a magnet, 144.
proportion between loadstone and iron, 149.
his error as to variation and longitude, 166.

præcession of the Æquinoxes, 234, 236.

primum mobile, the, 79, 214, 216, 218, 220, 226, 232, 237.
prostaphæresis, 174, 236.
Prutenical Tables, the, 235.
Ptolemæus, Claudius.

on loadstone fables, 2, 32.
on the occurrence of loadstone and of iron, 9,25.
on the dissolution of the earth, 91, 217, 218.
alleged relation of regions with the planets, 137.
on the elevation of the pole at different latitudes, 213, 214.
on the Primum Mobile, and the diurnal movement of the stars, 216, 228, 234.
on the anomalies of the earth's motion, 237.

Puteanus, Gulielmus (Du Puys), 3, 63.

pyrimachus (i.e., pyrites), 23.
Pythagoras, 57, 208.
pyxidula, 4, 181.
pyxis, 3, 115, 147, 165, 172.

Radius, the, of the earth's orbit, 218.
Rasis. See Rhazes.
rays of magnetick virtue, 95.
Reinoldus, Erasmus (or Rheinholdus), 213.
remora, the (or sucking fish), 7, 63, 110.
resin becomes electrical by friction, 48, 52.
respective points, 5, 153, 161, 162.
reversal of polarity, 101, 137.
revolution of the globe, 46, 81, 91, 220.
repulsion, electrical, denied to exist, 113.
Rhazes (Muhammad ibn Zakarīyā), 34, 35.
rings, on the verticity of, 129.
Rodriguez de Lagos, 177.
Rosetius Calaber, Hannibal, 3.
Ruellius, Joannes, 7.
Rueus, Franciscus (de la Rue), 6.

Saffron of Mars, 34, 91, 93.
sagda, or sagdo, the, 111.
Sanuto, Livio, 5, 153, 167.
sapphire, the, 48.
scales of iron, 22.
Scaliger, Julius Cæsar.

on cause of magnetick direction, 5, 64, 153.
on a fall of meteorick iron, 26.
on preservation of loadstones, 37.
on amber, 47.
on magnetick attraction, 70.
admits the loadstone to have a soul, 68.
on diamond attracting iron, 112.

scoria or slag of iron, 34, 35.

sealing wax is electrical, 48, 53.
Sebastian Cabot. See Cabot.
Serapio, or Serapio Mauritania (Yuhanná ibn Sarapion), 2, 6.
Severtius, Jacobus, 5.
shielding, magnetick, by iron plate, 83, 85.

siderites (σιδερίτης) 8, 11, 143.
siegelstein 11.
silk suspension for magnetick iron, 29, 30.
Silvaticus, Matthæus, 3.
silver, loadstone for, 109, 110.
similars, doctrine of attraction of, 50, 62.
Simon Stevinus, *v bis, 167, 168.
slate, magnetick properties of, 43.
smeargel (emery), 22.
Solinus, Caius Julius, 1, 9, 111.
Solomon the King, 4.
Sotacus, 9.
Stadius, 213.
stars are at various distances, 215.
steel, 23, 39, 69, 71, 93, 95, 147.
Stevinus, Simon, *v bis, 167, 168.
stomoma (στόμωμα) 23, 33, 36.
Strabo, 25.
succinum. See amber.
Sudini, or Sudavienses, 47.
sulphur, electrical by friction, 48, 53, 56, 59.
συνδρόμη, *vj.
συνεντελέχεια, 68.
Sussex, iron ore in, 22.
sympathy and antipathy, 65, 68, 112.

Tacitus, Cornelius, 25.
Taisner, or Taisnier, Joannes, 5, 107.
Tariassiona or Tarazona, 23.
terrella.

definition of, *vj, 12, 13.
poles and axis of, 13, 72, 81, 144.
divided into two parts, 72.
magnetick vigour, diagram of, 74, 75.
how small pieces of iron behave toward, 75, 76.
orbe of virtue of, 76, 77, 104.
"geography" of, 78.
æquinoctial circle of, 79, 144.
parallels of, 80, 211.
magnetick horizon of, 80.
proportion of the forces in, 81, 82.
experiment with iron sphere, 85.
small iron sphere and rod, 94, 102.
centre of magnetick virtue in, 95.
irregular terrella to exhibit variation, 155, 157.
to illustrate the dip of the needle, 190, 192.
analogy of, with the earth, 41, 78, 119, 211.

testing loadstones, methods of, 108.

Thales of Miletus, 11, 61, 68, 208, 210.
theamedes, the, 18.
Thebitius, or Thebit ben Korrah, 117, 236.
Themistius, 71.
Theophrastus, 1, 9, 11.
Thomas Aquinas, 3, 64.
tides, the cause of, 86.
Tycho Brahe, 174, 229.

Variation of the compass, 7, 46, 79, 116, 151-163, 166, 167, 180.
variation at the Azores, 4, 154, 156, 167.
versorium, magnetick, definition of, *vj.
use of, 13, 115, 147.
versorium, non-magnetick, use of, 48, 49, 50.
verticity, 28, 115, 119-147.

acquired, 67, 68, 84, 85, 104, 123, 125, 129, 138, 139, 141, 142, 211.
in iron plates touched by loadstone, 84.
in iron sphere, 85.
how, in iron, 123, 139, 212.
in bracket in tower of St. Augustine's Church, Rimini, 141.
similar at ends of rod touched in middle, 84, 129.
by percussion, 139.
through interposed matter, 67.
not in bodies other than magnetick, 142.
æquator separates two kinds of, 79.
possessed by the earth, as a "Cause," 117.
change of, through change of mass, 72.
definition of, *vj.
described, 119, 120, 121.
destroyed by heat, 66, 93, 124.
earth produces it in loadstone and iron, 42, 140, 211, 212.
excited through greater distances in iron than in air, 104.
exists in all shapes of loadstone, 76.
helps the earth to keep its orbit, 224.
inhærent in wrought iron, 31, 115.
as a magnetick motion, 46.
mutation of, 120, 137.
magnitude of earth prevents variation of, 163, 164.
none acquired by iron rubbed on æquator of terrella, 148.
not affected by position of loadstone, 144.
of one loadstone as affected by another, 69, 138.
opposite, acquired by iron touched by loadstone, 115, 125, 129.
parts having same repel, 122, 133.
pole of, where last contact is, 149.
strengthened in versoria, 147-150.
strength of, decreases at once in both poles, 146.

Villa nova, Arnaldus de, 2, 7.

vincentina, the, 48.
Vincent's Rock, gem of, 54.

Weather affects electricks, 48, 53, 55, 56.
weighing the magnetick force, 108.
Wright, Edward, his prefatory address, *iij bis, 7.
wrought iron is magnetick, 29, 139.

Youth preserved by loadstone, 32.

Zeilam, the king of, 32.
Zimiri, 11.
Zoroaster, 209.