ivre i. pt. ii. ch. cxx.):--"Por ce
nagent li marinier a l'enseigne des estoiles qui i sont, que il apelent
tramontaines, et les gens qui sont en Europe et es parties deca nagent a
la tramontaine de septentrion, et li autre nagent a cele de midi. Et qui
n'en set la verite, praigne une pierre d'aimant, et troverez que ele a
ij faces: l'une qui gist vers l'une tramontaine, et l'autre gist vers
l'autre. Et a chascune des ij faces la pointe d'une aguille vers cele
tramontaine a cui cele face gist. Et por ce seroient li marinier deceu
se il ne se preissent garde" (p. 147, Paris edition, 1863). Dante
(_Paradiso_, xii. 28-30) mentions the pointing of the magnetic needle
toward the pole star. In Scandinavian records there is a reference to
the nautical use of the magnet in the _Hauksbok_, the last edition of
the _Landnamabok_ (Book of the Colonization of Iceland):--"Floki, son of
Vilgerd, instituted a great sacrifice, and consecrated three ravens
which should show him the way (to Iceland); for at that time no men
sailing the high seas had lodestones up in northern lands."

Haukr Erlendsson, who wrote this paragraph about 1300, died in 1334; his
edition was founded on material in two earlier works, that of Styrmir
Karason (who died 1245), which is lost, and that of Hurla Thordson (died
1284) which has no such paragraph. All that is certain is a knowledge of
the nautical use of the magnet at the end of the 13th century. From T.
Torfaeus we learn that the compass, fitted into a box, was already in
use among the Norwegians about the middle of the 13th century (_Hist.
rer. Norvegicarum_, iv. c. 4, p. 345, Hafniae, 1711); and it is probable
that the use of the magnet at sea was known in Scotland at or shortly
subsequent to that time, though King Robert, in crossing from Arran to
Carrick in 1306, as Barbour writing in 1375 informs us, "na nedill had
na stane," but steered by a fire on the shore. Roger Bacon (_Opus majus_
and _Opus minus_, 1266-1267) was acquainted with the properties of the
lodestone, and wrote that if set so that it can turn freely (swimming on
water) it points toward the poles; but he stated that this was not due
to the pole-star, but to the influence of the northern region of the
heavens.

The earliest unquestionable description of a pivoted compass is that
contained in the remarkable _Epistola de magnete_ of Petrus Peregrinus
de Maricourt, written at Lucera in 1269 to Sigerus de Foncaucourt.
(First printed editio