=A.D. 1624.=--Gunter (Edmund), professor of astronomy at Gresham College, publishes his work “Of the Sector, Cross-Staff, and other Instruments,” at Chap. V of the second book of which he gives the result of the eight observations he made on the variation of the variation “in various parts of the ground” at Limehouse on the 13th of June, 1622. His observations of the declination, as given by Prof. Gellibrand, are detailed at Chap. I of Walker’s “Ter. and Cos. Mag.,” Cambridge, 1866. REFERENCES.--De La Rive, “Electricity,” etc., Vol. I. p. 165; Poggendorff, “Geschichte der Physik,” Leipzig, 1879, p. 275. =A.D. 1625.=--Carpenter (Nathaniel), Dean of Ireland, well-known mathematician, publishes at Oxford, “Geography delineated forth in two bookes, containing the sphæricall and topicall parts thereof,” wherein he thus alludes to Dr. Gilbert’s “De Magnete”: “Magneticall proprieties, I find in ancient writers, as little knowne as their causes; and if any matter herein were broached, it was merely conjectural, and depending on no certain demonstration; neither had we any certain or satisfactory knowledge of the thing vntill such time as it pleased God to raise vp one of our countrymen, D. Gilbert, who, to his euerlasting praise, hath trodden out a new path to Philosophie, and on the Loadstone, erected a large Trophie to commend him to posterity. This famous Doctor being as pregnant in witty apprehension as diligent in curious search of naturall causes, after many experiments and long enquiry, found the causes of most magneticall motions and proprieties hid in the magneticall _temper_ and constitution of the Earth, and that the earth it selfe was a meere magneticall body challenging all those proprieties, and more than haue expressed themselves in the Loadstone; which opinion of his was no sooner broached than it was embraced, and wel-commed by many prime wits as well English as Forraine. Insomuch that it hath of late taken large root and gotten much ground of our vulgar Philosophie.” REFERENCES.--“Nature,” September 26, 1901; “Dict. of Nat. Biogr.,” Vol. IX. pp. 161–162; Larousse, “Dict.,” Vol. IV. p. 438; Prince’s “Worthies” (1810), pp. 173–175, 603. =A.D. 1625.=--Naudé (Gabriel), a celebrated French savant and one of the most learned of his day, also physician to King Louis XIII, and an intimate friend of Gassendi, is the author of “Apologie pour tous,” etc. (“Apology for great men falsely accused of magic”), of which other editions appeared in 1652, 1669 and 1712. The magico-theosophical philosophy, as Madame Blavatsky expresses it, is fully indicated in his work, and he proved to be the warmest defender of the doctrines of occult magnetism, of which he was one of the first propounders.