Page 250 - Lanzarotto Malocello from Italy to the Canary Islands

250 from Italy to the Canary Islands

“non è pileggio da picciol barca /quel che fendendo va l’ardita prora”,
Paradiso, Canto XXIII vv. 67-68). Portolan charts also feature the nautical
medieval Italian navigation term “per starea”, meaning cabotage along the
coast, derived phonetically from the Greek “sterea ghe”, meaning terra fir-
ma. The oldest known medieval portolan chart showing the Mediterranean
th
is the Italian “Compasso de navigare” probably from the mid 13 century,
where the term “Compasso” comes from the Latin verb “compassare”, that
is, “measure by steps”. Concluding with portolan charts, we may men-
tion the “Codex Valedemar”, made for the routes from Scandinavia to the
islands of the North Atlantic, which is the oldest one to show the coasts
of that side of the Atlantic, whereas the first French portolan chart on the
Mediterranean, made in 1485 and reproduced several times until 1643, is
known as “le grant routier”.
Of course, there were also atlases, made of multiple maps. We should
definitely talk about the compass, which - according to Caddeo - is men-
tioned in a letter written in Lucera in Apulia in 1269, and mentioned again
in the on board inventory of the Messina ship “San Nicola” as “bussola
de ligno”, i.e. wooden compass. The origin of the compass is attributed to
both the Chinese and the Vikings, because it seems that for fun they threw
magnetized arrows at random, like rolling dice, and that these arrows
would “magically” point north. Others say that the compass went from the
Chinese to the Arabs and that the latter passed it on to sailors from Amalfi.
The compass probably comes from the pyxis nautica, a jar filled with water
inside which was a straw holding a floating needle of magnetized iron or
magnetite (which is a light blue mineral they used to call “adamantinus”).
This instrument had the drawback of the needle turning wildly when the
sea was not calm, on account of the mechanical force of the waves being
greater than the magnetic force of the needle. Eventually, some sailors dis-
covered that the clear and heavy boxwood greatly reduced the interference
of the waves, thus they decided to no longer put this instrument in water
but on a dry surface with a metal lynchpin placed at the centre of such a
needle with the whole thing closed inside a box of boxwood. The Italian
word for boxwood is “bosso”, which referring to the box of boxwood gen-
erated the term “bossolo”; “bussola” is the closely related Italian word for
compass. Italian sailors knew of the mariner’s astrolabe, as well as the
“Toleta de Martelojo”, a board divided into four columns that gave sine,
cosine, tangent and secant, allowing for navigation using simple geomet-
rical and algebraic calculations. Interestingly, the term “astrolabe” derives