is stone
amongst carbuncles, but it is much more probably _rubellite_, that is to
say, red tourmaline.

(6.) _Diamond._ In spite of the confusion already noted, _a propos_ of
_adamas_ (Note to p. 47), between loadstone and diamond, there seems to be
one distinct record of an attractive effect having been observed with a
rubbed diamond. This was recorded by Fracastorio, _De sympathia et
antipathia rerum_ (Giunta edition, Venice, MDLXXIIII, chap. v., p. 60
_verso_), "cujus rei & illud esse signum potest, cum confricata quaeda vt
Succinum, & Adamas fortius furculos trahunt." And (on p. 62 _recto_); "nam
si per similitudine (vt supra diximus) fit haec attractio, cur magnes non
potius magnetem trahit, [~q] ferrum, & ferrum non potius ad ferrum movetur,
quam ad magnetem? quae nam affinitas est pilorum, & furculorum cum Electro,
& Adamante? praesertim [~q] si cum Electro affines sunt, quomodo & cum
Adamante affinitatem habebunt, qui dissimilis Electro est?" An
incontestable case of the observation of the electrification of the diamond
occurs in Gartias ab Horto. The first edition of his _Historia dei Semplici
Aromati_ was publisht at Goa in India in 1563. In chapter xlviii. on the
Diamond, occur these words (p. 200 of the Venetian edition of 1616):
"Questo si bene ho sperimentato io piu volte, che due Diamanti perfetti
fregati insieme, si vniscono di modo insieme, che non di leggiero li potrai
separare. Et ho parimente veduto il Diamante dopo di esser ben riscaldato,
tirare a se le festuche, non men, che si faccia l'elettro." See also
Aldrovandi, _Musaeum Metallicum_ (Bonon., 1648, p. 947).

Levinus Lemnius also mentions the Diamond along with amber. See his
_Occulta naturae miracula_ (English edition, London, 1658, p. 199).

[119] PAGE 48, LINE 16. Page 48, line 18. _Iris gemma._--The name _iris_
was given, there can be little doubt, to clear six sided prisms of
rock-crystal (quartz), which, when held in the sun's beams, cast a crude
spectrum of the colours of the rainbow. The following is the account of it
given in Pliny, book xxxvii., chap. vii. (p. 623 of the English version of
1601):

"... there is a stone in name called Iris: digged out of the ground it is
in a certaine Island of the red sea, distant from the city Berenice three
score miles. For the most part it resembleth Crystall: which is the reason
that some hath tearmed it the root of Crystall. But the cause why they call
it Iris, is, That if the beames of the Su