CHAP. Whether the same be verified in the action of the III Sun upon inferiour bodies, whether there be Eolian Magnets, whether the flux and reflux of the Sea be caused by any Magnetism from the Moon; whether the like be really made out, or rather Metaphorically verified in the sympathies of Plants and Animals, might afford a large dispute; and Kircherus in his Catena Magnetica hath excellently discussed the same; which work came late unto our hand, but might have much advantaged this Discourse.

Other Discourses there might be made of the Loadstone: as Moral, Mystical, Theological; and some have handsomely done them; as Ambrose, Austine, Gulielmus Parisiensis, and many more, but these fall under no Rule, and are as boundless as mens inventions. And though honest minds do glorifie God hereby; yet do they most powerfully magnifie him, and are to be looked on with another eye, who demonstratively set forth its Magnalities; who not from postulated or precarious inferences, entreat a courteous assent; but from experiments and undeniable effects, enforce the wonder of its Maker.

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CHAPTER IV

Of Bodies Electrical.

AVING thus spoken of the Loadstone and Bodies Magnetical, I shall in the next place deliver somewhat of Electrical, and such as may seem to have attraction like the other. Hereof we shall also deliver what particularly spoken or not generally known is manifestly or probably true, what

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Electrical,

generally believed is also false or dubious. Now by CHAP. Electrical bodies, I understand not such as are Metallical, mentioned by Pliny, and the Ancients; for their Bodies Electrum was a mixture made of Gold, with the what? Addition of a fifth part of Silver; a substance now as unknown as true Aurichalcum, or Corinthian Brass, and set down among things lost by Pancirollus. Nor by Electrick Bodies do I conceive such only as take up shavings, straws, and light bodies, in which number the Ancients only placed Jet and Amber; but such as conveniently placed unto their objects attract all bodies palpable whatsoever. I say conveniently placed, that is, in regard of the object, that it be not too ponderous, or any way affixed; in regard of the Agent, that it be not foul or sullied, but wiped, rubbed, and excitated; in regard of both, that they be conveniently distant, and no impediment interposed. I say, all bodies palpable, thereby excluding fire, which indeed it will not attract, nor yet draw through it; for fire consumes its effluxions by which it should attract.

Now although in this rank but two were commonly mentioned by the Ancients, Gilbertus discovereth many more; as Diamonds, Saphyrs, Carbuncles, Iris, Opalls, Amethysts, Beril, Crystal, Bristol-stones, Sulphur, Mastick, hard Wax, hard Rosin, Arsenic, Sal-gemm, RochAllum, common Glass, Stibium, or Glass of Antimony. Unto these Cabeus addeth white Wax, Gum Elemi, Gum Guaici, Pix Hispanica, and Gipsum. And unto these we add Gum Anime, Benjamin, Talcum, Chinadishes, Sandaraca, Turpentine, Styrax Liquida, and Caranna dried into a hard consistence. And the same attraction we find, not onely in simple bodies, but such as are much compounded; as in the Oxycroceum plaister, and obscurely that ad Herniam, and Gratia

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CHAP. Dei; all which smooth and rightly prepared, will discover a sufficient power to stir the Needle, setled freely upon a well-pointed pin; and so as the Electrick may be applied unto it without all disadvantage.

But the attraction of these Electricks we observe to be very different. Resinous or unctuous bodies, and such as will flame, attract most vigorously, and most thereof without frication; as Anime, Benjamin, and most powerfully good hard Wax, which will convert the Needle almost as actively as the Loadstone. And we believe that all or most of this substance if reduced to hardness, tralucency or clearness, would have some attractive quality. But juices concrete, or Gums easily dissolving in water, draw not at all: as Aloe, Opium, Sanguis Draconis, Lacca, Calbanum, Sagapenum. Many stones also both precious and vulgar, although terse and smooth, have not this power attractive: as Emeralds, Pearl, Jaspis, Corneleans, Agathe, Heliotropes, Marble, Alablaster, Touchstone, Flint, and Bezoar. Glass attracts but weakly, though clear; some slick stones and thick Glasses indifferently: Arsenic but weakly, so likewise Glass of Antimony, but Crocus Metallorum not at all. Salts generally but weakly, as Sal Gemma, Allum, and also Talke; nor very discoverably by any frication, but if gently warmed at the fire, and wiped with a dry cloth, they will better discover their Electricities.

No Metal attracts, nor Animal concretion we know, although polite and smooth; as we have made trial in Elks Hoofs, Hawks-Talons, the Sword of a Sword-fish, Tortois-shells, Sea-horse, and Elephants Teeth, in Bones, in Harts-horn, and what is usually conceived Unicornshorn. No Wood though never so hard and polished, although out of some thereof Electrick bodies proceed;

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as Ebony, Box, Lignum vitæ, Cedar, etc. And although CHAP. Jet and Amber be reckoned among Bitumens, yet neither do we find Asphaltus, that is, Bitumens of Judea, nor Sea-cole, nor Camphire, nor Mummia to attract, although we have tried in large and polished pieces. Now this attraction have we tried in straws and paleous bodies, in Needles of Iron, equilibrated, Powders of Wood and Iron, in Gold and Silver foliate. And not only in solid but fluent and liquid bodies, as oyls made both by expression and distillation; in Water, in spirits of Wine, Vitriol and Aquafortis.

But how this attraction is made, is not so easily determined; that 'tis performed by effluviums is plain, and granted by most; for Electricks will not commonly attract, except they grow hot or become perspirable. For if they be foul and obnubilated, it hinders their effluxion; nor if they be covered, though but with Linen or Sarsenet, or if a body be interposed, for that intercepts the effluvium. If also a powerful and broad Electrick of Wax or Anime be held over fine powder, the Atoms or small particles will ascend most numerously unto it; and if the Electrick be held unto the light, it may be observed that many thereof will fly, and be as it were discharged from the Electrick to the distance sometime of two or three inches. Which motion is performed by the breath of the effluvium issuing with agility; for as the Electrick cooleth, the projection of the Atoms ceaseth.

attraction

Electrick.

The manner hereof Cabeus wittily attempteth, affirm- Cabeus his ing that this effluvium attenuateth and impelleth the way for neighbor air, which returning home in a gyration, in bodies carrieth with it the obvious bodies unto the Electrick. And this he labours to confirm by experiments; for if the straws be raised by a vigorous Electrick, they do

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CHAP. appear to wave and turn in their ascents. If likewise the Electrick be broad, and the straws light and chaffy, and held at a reasonable distance, they will not arise unto the middle, but rather adhere toward the Verge or Borders thereof. And lastly, if many straws be laid together, and a nimble Electrick approach, they will not all arise unto it, but some will commonly start aside, and be whirled a reasonable distance from it. Now that the air impelled returns unto its place in a gyration or whirling, is evident from the Atoms or Motes in the Sun. For when the Sun so enters a hole or window, that by its illumination the Atoms or Motes become perceptible, if then by our breath the air be gently impelled, it may be perceived, that they will circularly return and in a gyration unto their places again.

The way of
Sir Kenelm

Digby.

Another way of their attraction is also delivered; that is, by a tenuous emanation or continued effluvium, which after some distance retracteth into it self; as is observable in drops of Syrups, Oyl, and seminal Viscosities, which spun at length, retire into their former dimensions. Now these effluviums advancing from the body of the Electrick, in their return do carry back the bodies whereon they have laid hold within the Sphere or Circle of their continuities; and these they do not onely attract, but with their viscous arms hold fast a good while after. And if any shall wonder why these effluviums issuing forth impel and protrude not the straw before they can bring it back, it is because the effluvium passing out in a smaller thred and more enlengthened filament, it stirreth not the bodies interposed, but returning unto its original, falls into a closer substance, and carrieth them back unto it self. And this way of attraction is best received, embraced