[244] Page 215, line 27. Page 215, line 24. quæ ... in cælo varijs distantijs collocata sunt.—This remark appears to be Gilbert's one contribution to the science of Astronomy; the stars having previously been regarded as fixed in the eighth sphere all at the same distance from the central earth, around which it revolved.
[245] Page 220, line 6. Page 220, line 6. quem nycthemeron vocamus.—The 1628 and 1633 editions read nyctemoron.
[246] Page 221, line 10. Page 221, line 11. poli verè oppositi sint.—For verè, the 1628 and 1633 editions read rectæ. All editions read sint, though sunt seems to make better sense.
[247] Page 223, line 7. Page 223, line 8. ad telluris conformitatem.—The word conformitas is unknown in classical Latin.
[248] Page 223, line 16. Page 223, line 17. Omitto quod Petrus Peregrinus constanter affirmat, terrellam super polos suos in meridiano suspensam, moveri circulariter integrâ revolutione 24 horis: Quod tamen nobis adhuc videre non contingit; de quo motu etiam dubitamus.
This statement that a spherical loadstone pivotted freely with its axis parallel to the earth's axis will of itself revolve on its axis once a day under the control of the heavens, thus superseding clocks, is to be found at the end of chap. x. of Peregrinus's Epistola De Magnete (Augsb., 1537).
Gilbert, who doubted this experiment because of the stone's own weight is taken to task by Galileo, in the third of his Dialogues, for his qualified admission.
"I will speak of one particular, to which I could have wished that Gilbert had not lent an ear; I mean that of admitting, that in case a little Sphere of Loadstone might be exactly librated, it would revolve in it self; because there is no reason why it should do so" (p. 376 of Salusbury's Mathematical Collections, London, 1661). The Jesuit Fathers who followed Gilbert, but rejected his Copernican ideas, pounced upon this pseudo-experiment, as though by disproving it they had upset the Copernican theory.
[249] Page 227, line 6. Page 227, line 7. This line is left out in the 1628 edition. In the 1633 edition it was also left out by the printer, and subsequently printed in in the margin, being page 219 of that edition.
[250] Page 234, line 35. Page 234, line 40. vt poli telluris respectus à polis.—If it may be permitted to read respectu for respectus the sense is improved, and the passage may then be translated thus: "that just as it was needful ... that the poles of the Earth as to direction should be 23 degrees and more from the poles of the Ecliptick; so now, &c."