418 teofilo f. ruiz
into the Atlantic, these advantages partly disappeared once one sailed south of the
equator, as the Portuguese began to do by mid-fifteenth century. Astrolabes had been
known in the West since the Middle Ages, but how to determine your latitude by
careful sightings of the sun at midday was never an easy thing to do, often requiring
landing to allow an accurate observation. By the 1470s, thanks to Abraham
Zacuto’s work, these difficulties were overcome. Zacuto was born in Salamanca in
1452 and studied and taught astronomy there and elsewhere. Fleeing Spain after the
Edict of Expulsion of the Jews in 1492, Zacuto went to Portugal. There he received
a warm welcome from the Portuguese court and saw his most influential work, the
Almanach perpetuum, translated into Portuguese. His development of a new astro-
labe and the information of the sun’s declination allowed for a more accurate fixing of
one’s position even south of the equatorial line. Vasco da Gama carried both Zacuto’s
more efficient astrolabe and the tables in his voyage to India. As a kind of denoue-
ment to this story, Zacuto went, once again, into exile after the forced conversion of
Portuguese Jews, traveled to North Africa (Tunis) and died in or near Jerusalem, a
remarkable example of the connections and contacts between the Mediterranean and
the Atlantic (Cantera Burgos, 1931).
ShipsIt is a platitude to posit Mediterranean ships as mostly heavy galleys powered by oars
and the harsh rowing of enslaved rowers. Galleys did ply the waters of the Mediterranean,
mostly engaged in naval warfare, but most navigation of the Mediterranean was done
by sail, undertaken by small vessels (barques, caravels) engaged in coastal sailing, and
connecting the different regions or “micro-economies’ of the Mediterranean. Yet,
cogs, for example, a type of ship developed in the Atlantic and the Baltic that could be
oared but depended mostly on sail power, appeared in Mediterranean sources only in
the fourteenth century, coinciding with the opening of the Straits to navigation and
confirming the importance of that event in the history of the Mediterranean. Hulks,
also of northern provenance, made their way into the Mediterranean in the late Middle
Ages. Clearly ship design and ship construction resulted from the amalgamation of
seafaring technologies from both the North Atlantic and the Christian and Islamic
Mediterranean (see also Gertwagen, this volume).
In the opening of the Atlantic to exploration, no other development would be as
important as the Portuguese combination of ships designed for Atlantic sailing with
the lateen sail of Mediterranean origin. The caravels that crossed the Atlantic and
reached India consolidated aspects of northern ship technology with Mediterranean
rigging. In this and many other developments, the Portuguese led the way. The
caravel deployed the lateen sail, allowing for easier tacking to the wind and freeing
the ships from a dependency on oars as the main source of power. Whether the
caravela redonda, combining square with lateen sails, or the caravela latina,
depending exclusively on lateen sails, these types of ships, followed by carracks and
galleons, would dominate the Atlantic. These technological advances propelled the
Portuguese and, eventually, the Castilians to gain a short-lived hegemony in the
Atlantic and the Indian Ocean. Together with the Portuguese introduction of
broadside artillery, that is, the use of artillery on board the ships (probably in the
1470 s), these technical innovations led to the rise of Atlantic powers that had now