Page:Mathematical collections and translations, in two tomes - Salusbury (1661).djvu/395

 stronger of which Poles is that which looketh towards the South. Observe, in the next place, that in a little Magnet this South and more vigorous Pole, becometh weaker, when ever it is to take up an iron in presence of the North Pole of another much bigger Magnet: and not to make any tedious discourse of it, assertain your self, by experience, of these and many other properties described by Gilbert, which are all so peculiar to the Magnet, as that none of them agree with any other matter. Tell me now, Simplicius, if there were laid before you a thousand pieces of several matters, but all covered and concealed in a cloth, under which it is hid, and you were required, without uncovering them, to make a guesse, by external signes, at the matter of each of them, and that in making trial, you should hit upon one that should openly shew it self to have all the properties by you already acknowledged to reside onely in the Magnet, and in no other matter, what judgment would you make of the essence of such a body? Would you say, that it might be a piece of Ebony, or Alablaster, otor [sic] Tin.

I would say, without the least hæsitation, that it was a piece of Load-stone.

If it be so, say resolutely, that under this cover and scurf of Earth, stones, metals, water, &c. there is hid a great Magnet, forasmuch as about the same there may be seen by any one that will heedfully observe the same, all those very accidents that agree with a true and visible Globe of Magnet; but if no more were to be seen than that of the Declinatory Needle, which being carried about the Earth, more and more inclineth, as it approacheth to the North Pole, and declineth lesse towards the Equinoctial, under which it finally is brought to an Æquilibrium, it might serve to perswade even the most scrupulous judgment. I forbear to mention that other admirable effect, which is sensibly observed in every piece of Magnet, of which, to us inhabitants of the Northern Hemisphere, the Meridional Pole of the said Magnet is more vigorous than the other; and the difference is found greater, by how much one recedeth from the Equinoctial; and under the Equinoctial both the parts are of equal strength, but notably weaker. But, in the Meridional Regions, far distant from the Equinoctial, it changeth nature, and that part which to us was more weak, acquireth more strength than the other: and all this I confer with that which we see to be done by a small piece of Magnet, in the presence of a great one, the vertue of which superating the lesser, maketh it to become obedient to it, and according as it is held, either on this or on that side the Equinoctial of the great one, maketh the self same mutations, which I have said are made by every Magnet, carried on this