From Conquerors: How Portugal Forged the First Global Empire, by Roger Crowley (Random House, 2015), Kindle pp. 34-40:
What Münzer witnessed [in 1497] was not just a glimpse of an exotic world beyond the earth’s curve but the industrial infrastructure of shipbuilding, seafaring provision, and arsenal facilities that gave Portugal its maritime punch. He saw
an enormous workshop with many furnaces where they make anchors, colubrinas [cannons] and so on, and everything necessary for the sea. There were so many blackened workers around the furnaces that we thought ourselves to be among the Cyclops in the cave of Vulcan. Afterward we saw in four other buildings innumerable very large and superb colubrinas, and also throwing weapons, javelins, shields, breastplates, mortars, hand guns, bows, lances—all very well made and in great abundance…and what enormous quantities of lead, copper, saltpetre and sulfur!
The ability to produce high-quality bronze cannons and techniques for deploying them effectively at sea had probably been developed by the energetic King João, whose inquisitive mind and wide-ranging interests included practical experiments in shipborne artillery. He had developed the use of large bombards on caravels and carried out test firings to determine their most effective use on the decks of pitching ships. The solution was to fire the guns horizontally at water level; any higher and the likelihood was that the shots would whistle overhead. In some cases, if the guns were positioned sufficiently low down in the bows, the cannonballs could be made to ricochet off the surface of the water, thus increasing their range. The Portuguese also developed berços, lightweight breech-loaded bronze swivel guns, which could be carried by ship’s boats and had the advantage over the conventional muzzle-loaders in their rate of fire—up to twenty shots an hour. The superiority of their artillery, which was augmented by recruitment of German and Flemish cannon founders and gunners, was to prove a telling advantage in the events about to unfold.
The expedition in prospect was modest in scale but carefully prepared. It was based on decades of incremental learning. All the skill and knowledge acquired over many years in ship design, navigation, and provision for Atlantic voyages went into building two stout ships, and [King] Manuel drew on a talented generation of practical experience in their construction. The caravel had been the agent and instrument of all this exploration, ideal for nosing up tropical rivers and battling back up the African coast against the wind, but horribly uncomfortable on long voyages across huge seas. Dias’s rounding of the Cape had exposed their operational limits: the crews would go no farther.
…
It was Dias who was charged with designing and overseeing the construction of two stout carracks, the sailing ships the Portuguese called naus, to lead the voyage. The brief was clear: they had to be durable enough to withstand the pounding seas of the southern Atlantic; roomy enough to accommodate and provision the crews better than the rolling decks of a caravel; small enough to maneuver in shallows and harbors. The ships under construction on the banks, their frameworks chocked up by wooden scaffolding, had tubby rounded hulls, high sides, a tall aftercastle, and three masts; they were nevertheless of shallow draft, and not outsized. They were about eighty feet long, and each probably weighed about 100 to 120 tons. Their square sails made them less maneuverable in a contrary wind; the compensation was their sturdiness against the unpredictable battering of unknown seas. A supply ship, intended to be broken up near the Cape, was also constructed.
It seems that no expense was spared in the construction or provisioning of these ships, or the recruitment and payment of the crews. “They were built by excellent masters and workmen, with strong nails and wood,” remembered the mariner Duarte Pacheco Pereira.
Each ship had three sets of sails and anchors and three or four times as much other tackle and rigging as was usual. The cooperage of the casks, pipes and barrels for wine, water, vinegar and oil was strengthened with many hoops of iron. The provisions of bread, wine, flour, meat, vegetables, medicines, and likewise of arms and ammunition, were also in excess of what was needed for such a voyage. The best and most skillful pilots and mariners in Portugal were sent on this voyage, and they received, besides other favors, salaries higher than those of any seamen of other countries. The money spent on the few ships of this expedition was so great that I will not go into detail for fear of not being believed.
The barrels rolled up the gangplanks on the shores of the dockyard contained sufficient food for three years. Gama received two thousand gold cruzados for the venture, a huge sum; his brother Paulo, the same. The seamen’s wages were raised, and some of the money paid in advance to support their families. It was perhaps a recognition that many of them would not be coming back. No detail was omitted. The ships carried the best navigational aids available: as well as sounding leads and hourglasses, astrolabes and the most up-to-date maps—and possibly copies of Abraham Zacuto’s recently printed tables for determining latitudes from the height of the sun. Twenty cannons were hoisted aboard, both large bombards and the smaller breech-loaded berços, along with plentiful supplies of gunpowder tightly sealed against the sea air and quantities of cannonballs. The skilled craftsmen—carpenters, caulkers, forgers of iron, and barrelmakers—who would ensure the security of the ships were recruited in pairs, in case death thinned out their ranks. There were interpreters to speak Bantu and Arabic; musicians to lead sea chanteys and blow ceremonial fanfares; gunners and men-at-arms and skilled seamen, supported by an underclass of “deck fodder.” These comprised African slaves, orphans, converted Jews, and convicted men, enrolled for the menial heavy work: hauling on ropes, raising anchors and sails, pumping out the bilges. The convicts were particularly expendable; they had been released from prison specifically to be put ashore to make first inquiries on uncharted and potentially hostile coasts; priests also went, to lead the prayers and consign the souls of the dead to the sea with a Christian burial.
There were four ships in all: the two carracks, christened São Gabriel and São Rafael after the archangels, according to a vow made by King João before his death; with them went a caravel, the Bérrio, and the two-hundred-ton supply ship. Gama called on seamen he knew and relatives he could trust, to lessen the possibility of dissent in a tightly knit expedition. These included his brother Paulo, commander of the Rafael, and two Gama cousins. His pilots and leading seamen were the most experienced of the age. They included Pêro de Alenquer and Nicholas Coelho, who had rounded the cape with Bartolomeu Dias, and Dias’s own brother Diogo. Another pilot, Pêro Escobar, whose name was carved at the Yellala Falls, had been a navigator with Diogo Cão. Bartolomeu Dias was also scheduled to accompany the expedition on the first leg of the voyage in a ship bound for the Guinea coast.
Far Outliers 