_Placit. Philos._, III. 7. The
latter {61} passage may be compared with Aristotle, _De Coelo_, II. 13,
who, referring to the followers of Pythagoras, says: "They say that the
middle is fire, that the earth is a star, and that it is moved circularly
about this centre; and that by this movement it produces day and night."

[243] PAGE 214, LINE 34. Page 214, line 42. _Copernicus._--His work is _De
revolutionibus orbium coelestium, libri vi._ (Basil., 1566).

[244] PAGE 215, LINE 27. Page 215, line 24. _quae ... in caelo 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 vere oppositi sint._--For
_vere_, the 1628 and 1633 editions read _rectae_. 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 integra 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 t