ar la adoperare,
_E dirizzar lo ago in ver la stella._

We cannot be diverted, by the nonsensical theory these lines contain,
from perceiving the positive testimony of the last verse to the poet's
knowledge of the polarity of the magnet. But if any doubt could remain,
Tiraboschi (t. iv. p. 171) has fully established, from a series of
passages, that this phenomenon was well known in the thirteenth century;
and puts an end altogether to the pretensions of Flavio Gioja, if such a
person, ever existed. See also Macpherson's Annals, p. 364 and 418. It
is provoking to find an historian like Robertson asserting, without
hesitation, that this citizen of Amalfi was the inventor of the compass,
and thus accrediting an error which had already been detected.

It is a singular circumstance, and only to be explained by the obstinacy
with which men are apt to reject improvement, that the magnetic needle
was not generally adopted in navigation till very long after the
discovery of its properties, and even after their peculiar importance
had been perceived. The writers of the thirteenth century, who mention
the polarity of the needle, mention also its use in navigation; yet
Capmany has found no distinct proof of its employment till 1403, and
does not believe that it was frequently on board Mediterranean ships at
the latter part of the preceding age. Memorias Historicas, t. iii. p.
70. Perhaps however he has inferred too much from his negative proof;
and this subject seems open to further inquiry.

[613] Boucher supposes it to have been compiled at Barcelona about 900;
but his reasonings are inconclusive, t. i. p. 72; and indeed Barcelona
at that time was little, if at all, better than a fishing-town. Some
arguments might be drawn in favour of Pisa from the expressions of Henry
IV.'s charter granted to that city in 1081. Consuetudines, quas habent
de mari, sic iis observabimus sicut illorum est consuetudo. Muratori
Dissert. 45. Giannone seems to think the collection was compiled about
the reign of Louis IX. 1. xi. c. 6. Capmany, the last Spanish editor,
whose authority ought perhaps to outweigh every other, asserts and seems
to prove them to have been enacted by the mercantile magistrates of
Barcelona, under the reign of James the Conqueror which is much the same
period. Codigo de las Costumbres Maritimas de Barcelona, Madrid, 1791.
But, by whatever nation they were reduced into their present form, these
laws were certainly the anc