A Deſcription of the Iſlands of St. Thome, Del Principe, and Annobono.
As the Portugueſe were the great Improvers of Navigation, and the firſt Europeans who traded too and ſettled on the Coaſts of Africa, even round to India, and made thoſe Diſcoveries, which now turn ſo much to the Advantage of other Nations, it may not be amiſs, previouſly to a Deſcription of thoſe Iſlands, to hint on that wonderful Property of the Loadſtone, that a little before had been found out, and enabled them to purſue ſuch new and daring Navigations.
The attractive Power of the Loadſtone, was univerſally known with the Ancients, as may be believed by its being a native Foſſil of the Grecians, (Magnes a Magneſia) but its directive, or polar Virtue, has only been known to us within this 350 Years, and ſaid to be found out by John Goia of Malphi, in the Kingdom of Naples, Prima dedit nautis uſum magnetis Amalphi
; tho’ others think, and aſſure us, it was tranſported by Paulus Venetus from China to Italy, like the other famous Arts of modern Uſe with us, Printing and the Uſe of Guns.
The other Properties of Improvements of the Magnet, viz. Variation, or its Defluction from an exact N. or S. Line, Variation of that Variation, and its Inclination, were the Inventions of Sebaſtian Cabot, Mr. Gellibrand, and Mr. Norman; the Inclination of the Needle, or that Property whereby it keeps an Elevation above the Horizon, in all Places but under the Equator, (where its Parallel) is as ſurprizing a Phænomenon as any, and was the Diſcovery of our Countrymen; and could it be found regular, I imagine would very much help towards the Diſcovery of Longitude, at leaſt would
