The Magnetic Coition, Attraction of Amber

Physicians, with the authority of Galen, wanted to confirm the belief in the attraction of purgative medicines through the juices.

• It was a truly vain and useless error

But they were ignorant that the causes of magnetical motions are widely different from the forces of amber.

For in other bodies, a conspicuous force of attraction manifests itself otherwise than in loadstone.

The Greeks call it ἤλεκτρον because it attracts straws to itself, when it is warmed by rubbing.

Then it is called ἅρπαξ and χρυσοφόρον from its golden colour.

But the Moors call it Carabe, because they offer the same in sacrifices and in the worship of the Gods.

Carab signifies ’to offer’ in Arabic. So Carabe is an offering.

Caliger quotes from Abohalis as seizing chaff, as S, out of the Arabic or Persian language.

Some also call it Amber, especially the Indian and Ethiopian amber, called in Latin Succinum, as if it were a juice.

The Sudavienses or Sudini call it geniter, as though it were generated terrestrially.

Amber comes for the most part from the sea.

• The rustics collect it on the coast after the more violent storms, with nets and other tackle; as among the Sudini of Prussia.
• It is also found sometimes on the coast of our own Britain.

It seems to be:

• produced also in the soil and at spots of some depth, like other bitumens
• washed out by the waves of the sea
• concreted more firmly from the nature and saltness of the sea-water

For it was at first a soft and viscous material.

Wherefore also it contains enclosed and entombed in pieces of it, shining in eternal sepulchres, flies, grubs, gnats, ants; which have all flown or crept or fallen into it when it first flowed forth in a liquid state.

Many modern authors have copied from others about amber and jet attracting chaff and other substances generally unknown.

It is not only amber and jet which entice small bodies.

• Diamond, Sapphire, Carbuncle, Iris gem, Opal, Amethyst, Vincentina, and Bristolla (an English gem or spar), Beryl, and Crystal do the same.

Similar powers of attraction are seen also to be possessed by:

• glass
  • glass (especially when clear and lucid)
  • false gems made of glass or Crystal
  • glass of antimony, and
  • many kinds of spars from the mines, and by Belemnites.
• Sulphur
• mastick
• hard sealing-wax[122] compounded of lac tinctured of various colours.
• hard resin
• orpiment[123], but less strongly

Less attractive are:

• Rock salt
• muscovy stone
• rock alum.

These latter do it with difficulty also and indistinctly under a suitable dry sky,

We can see this when the air is sharp and clear and rare in mid-winter, when the emanations from the earth hinder electricks less.

The electrick bodies become more firmly indurated; about which hereafter.

These substances draw everything, not straws and chaff only, but all metals, woods, leaves, stones, earths, even water and oil, and everything which is subject to our senses, or is solid.

Alexander Aphrodiseus falsely declares the question of amber to be inexplicable because it attracts dry chaff only and not basil leaves.

To test how such attraction occurs, make yourself a versorium of any metal 4 digits in length.

Resting it lightly on its point of support after the manner of a magnetick needle, to one end of which bring up a piece of amber or a smooth Versorium and polished gem which has been gently rubbed; for the versorium turns forthwith.

This attraction is not so much a singular property of a few things as is commonly supposed.

But it is the nature of very many, both of simple substances, remaining merely in their own form, and of compositions, as of hard sealing-wax, & of certain other mixtures besides, made of unctuous stuffs.

Where does this attraction come from?

By Galen, 3 kinds of attractives were recognized in nature:

1. Substances which attract by their elemental quality, namely, heat
2. Substances which attract by the succession of a vacuum
3. Substances which attract by a property of their whole substance, which are also quoted by Avicenna and others.

These classes, however, are not satisfactory.

They neither embrace the causes of:

• amber, jet, diamond and similar substances
• the loadstone and all magnetick substances
  • These get their virtue by a very dissimilar and alien influence from them, derived from other sources.

Amber truly does not allure by heat. If warmed by fire and brought near straws, it does not attract them.

Cardan (as also Pictorio) reckons that this happens in no different way than with the cupping-glass, by the force of fire.

Yet the attracting force of the cupping-glass does not really come from the force of fire.

But he had previously said that the dry substance wished to imbibe fatty humour, and therefore it was borne towards it. But these statements are at variance with one another, and also foreign to reason.

For if amber had moved towards its food, or if other bodies had inclined towards amber as towards provender, there would have been a diminution of the one which was devoured, just as there would have been a growth of the other which was sated. Then why should an attractive force of fire be looked for in amber?

If the attraction existed from heat, why should not very many other bodies also attract, if warmed by fire, by the sun, or by friction?

Neither can the attraction be on account of the dissipating of the air, when it takes place in open air (yet Lucretius the poet adduces this as the reason for magnetical motions).

Nor in the cupping-glass can heat or fire attract by feeding on air: in the cupping-glass air, having been exhausted into flame, {50}when it condenses again and is forced into a narrow space, makes the skin and flesh rise in avoiding a vacuum.

In the open air warm things cannot attract, not metals even or stones, if they should be strongly incandescent by fire. For a rod of glowing iron, or a flame, or a candle, or a blazing torch, or a live coal, when they are brought near to straws, or to a versorium, do not attract; yet at the same time they manifestly call in the air in succession; because they consume it, as lamps do oil.

But concerning heat, how it is reckoned by the crowd of philosophizers, in natural philosophy and in materia medica to exert an attraction otherwise than nature allows, to which true attractions are falsely imputed, we will discuss more at length elsewhere, when we shall determine what are the properties of heat and cold.

They are very general qualities or kinships of a substance, and yet are not to be assigned as true causes, and, if I may say so, those philosophizers utter some resounding words; but about the thing itself prove nothing in particular.

Nor does this attraction accredited to amber arise from any singular quality of the substance or kinship, since by more thorough research we find the same effect in very many other bodies; and all bodies, moreover, of whatever quality, are allured by all those bodies.

Similarity also is not the cause; because all things around us placed on this globe of the earth, similar and dissimilar, are allured by amber and bodies of this kind; and on that account no cogent analogy is to be drawn either from similarity or identity of substance.

But neither do similars mutually attract one another, as stone stone, flesh flesh, nor aught else outside the class of magneticks and electricks. Fracastorio would have it that “things which mutually attract one another are similars, as being of the same species, either in action or in right subjection.