lzevir, 1651), in Lib. v., the
part which in the manuscript was left in English, and was turned into Latin
by his brother. It comprises about fifteen quarto pages, from Cap. X. to
Cap. XIX. inclusive, beginning with a characteristic diatribe against
Taisnier, Levinus Lemnius, and Scaliger. But in assigning causes he himself
goes wide of the mark. Proceeding by a process of elimination he first
shows that the moon's light cannot be the cause that impels the tides.
"Luna," he says, "non radio, non lumine, maria impellit. quomodo igitur?
Sane corporum conspiratione, acque (ut similitudine rem exponam) Magnetica
attractione." This cryptic utterance he proceeds to explain by a diagram,
and adds: "Quare Luna non tam attrahit mare, quam humorem & spiritum
subterraneum; nec plus resistit interposita terra, quam mensa, aut quicquam
aliud densum, aut crassum, magnetis viribus."

[173] PAGE 87, LINE 7. Page 87, line 9. _armatura._--Here this means the
cap or snout of iron with which the loadstone was armed. This is apparently
the first use of the term in this sense.

In the _Dialogues of Galileo_ (p. 369 of Salusbury's _Mathematical
Collections_, Dialogue iii.), Sagredus and Salviatus discuss the arming of
the loadstone, and the increased lifting power conferred by adding an iron
cap. Salviatus mentions a loadstone in the Florentine Academy which,
unarmed, weighed six ounces, lifting only two ounces, but which when armed
took up 160 ounces. Whereupon Galileo makes Salviatus say: "I extreamly
praise, admire, and envy this Authour, for that a conceit so stupendious
should come into his minde. ... I think him [_i.e._, Gilbert] moreover
worthy of extraordinary applause for the many new and true Observations
that he made, to the disgrace of so many fabulous Authours, that write not
only what they do not know, but whatever they hear spoken by the foolish
vulgar, never seeking to assure themselves of the same by experience,
perhaps, because they are unwilling to diminish the bulk of their Books."

[174] PAGE 87, LINE 12. Page 87, line 15. The reference to _lib._ 3 is {48}
a misprint for _lib._ 2. It is corrected in the edition of 1633, but not in
that of 1628.

[175] PAGE 87, LINE 17. Page 87, line 21. _conactu._--The editions of 1628
and 1633 read _conatu_.

[176] PAGE 88, LINE 2. Page 88, line 3. _Coitio vero non fortior._--This
heading to chap. xix., taken with the seven lines that follow, and the
contrast drawn between _unitio_ a