On the magnet, magnetick bodies also, and on the great magnet the earth / a new physiology, demonstrated by many arguments & experiments

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[199] Page 118, line 15. Page 118, line 13. nam æquè potens est.—Later observation showed this view to be incorrect. The horizontal component of the earth's magnetic field is not equally strong all over the globe, and the sluggishness of the needle's return to its position of rest is not due to the supporting pin becoming blunt with wear. The value of the horizontal component is zero at the north magnetic pole, and increases toward the magnetic equator. It is greatest near Singapore and in Borneo, being there more than twice as great as it is at London. (See Captain Creak in Report of Voyage of H.M.S. Challenger, Physics and Chemistry, vol. ii., part vi., 1889.)

[200] Page 119, line 5. Page 119, line 2. lapis.—Both Stettin editions read lapidis.

[201] Page 119, lines 9-11. Page 119, lines 7-9. The gist of the whole book is summarized in these lines. They furnish a cardinal example of that inductive reasoning which was practist by Gilbert, and of which Bacon subsequently posed as the apostle. Compare pages [41] and [211].

[202] Page 120, line 8. Page 120, line 5. dicturi sumus.—Change of verticity is treated of in book iii., chap. x., pp. [137] to [140].

[203] Page 125, line 24. Page 125, line 29. appositam.—All editions give this word, though the sense requires appositum.

[204] Page 128, line 9. Page 128, line 11. non nimis longum.—The editions of 1628 and 1633 read (wrongly) minus instead of nimis.

[205] Page 130, line 12. Page 130, line 14. The word hunc in the folio of 1600 is corrected in ink to tunc, and the Stettin editions both read tunc.

[206] Page 132, line 9. Page 132, line 10. minimus & nullius ponderis.—The editions of 1628 and 1633 both wrongly read est for &.

[207] Page 132, line 28. Page 133, line 1. nutat.—The editions of 1628 and 1633 both wrongly read mutat.

[208] Page 134, line 22. Page 134, line 25. in rectâ sphærâ.—The meaning of the terms a right or direct sphere, an oblique sphere and a parallel sphere are explained by Moxon on pages 29 to 31 of his book A Tutor to Astronomy and Geography (Lond., 1686):