In the year 150 A.D., the learned Alexandrian Claudius Ptolemy had made a map of Europe and of those parts of Asia and Africa which were then known, or supposed to exist; and on that map, for the first time in history, the world was represented as a sphere—though a stationary one. Therefore, speculated those who thought about it at all, assuming Ptolemy’s theory to be correct, how could a mariner, even were he successful in navigating his vessel down the awful declivity on one side of the globe, hope to make it climb up again on the other? How could he cross the equator, which Aristotle and Pliny had declared was an uninhabitable zone, so torrid that the earth around was burnt up as with fire and only marine salamanders, if such monsters existed, could live in the super-heated waters? And, even if the equator were passable, how could the frightful abysses into which the ocean was supposed to discharge itself at the pole be escaped?
Some time in the sixth century a monk named Cosmas had attempted to answer these questions by means of a theory evolved from a study of the Bible and more consistent with its descriptions and metaphors. In the map he made, the world was represented as a level rectangle, its sides composed of blue walls, supporting a dome that separated the mortal domain from the Paradise where dwelt the Creator and his angels; and, fanciful as was this cosmos of Cosmas’ devising, his map was regarded as the standard of geographical knowledge down to the time of Columbus. Even after his time the famous astronomer Galileo was imprisoned as a heretic partly for reasserting the theory of Ptolemy. No one but a few scientists even imagined that the east could be reached by sailing west; no one, not even they, yet knew that Africa could be circumnavigated and the treasures of gorgeous Far Cathay (as China was then called) brought to Europe’s doors by water. Yet it was to accomplish that very object that the series of voyages was begun that led eventually to the discovery of America.
Venice and Genoa, grown rich and powerful through trade with India and the nearer countries of the Orient, had for a space enjoyed a prosperity and revival of culture that were felt throughout Christendom. Then had come the conquest of Spain and domination of the Mediterranean by the Moors, and, afterward, the wars of the Crusades, which had checked the Saracen advance but interrupted all other commerce with the infidels. Meanwhile, as though to compensate for this loss, the great Mongolian conqueror Genghis Khan had fulfilled his remarkable destiny and, instead of adopting measures to prevent it, invited western intercourse with the countries he had brought under his sway, and China, about which almost nothing was then generally known, was visited overland by traders, adventurers, and missionaries. Marco Polo, a Venetian, after spending more than twenty years in the far east, part of the time in the service of the Great Khan Kubilay, had returned by way of India and Persia, laden with jewels of enormous value, and had written a book descriptive of the countries he had seen and the wealth and customs of the people. In the fourteenth century, when the Mongolian dynasty was overthrown, the Asiatics had again turned hostile and the land route was closed.
But during this open season it had become known that Cathay was not the end of the world, as had been supposed—that there was an ocean beyond and the wonderful Island of Cipango (Japan) and other islands rich in spices and costly products; and Europe began to wonder, since the Tartars barred the route by land, whether these desirable places might not be accessible by water. “Between wondering and the attempt,” says Hawthorne, “there was a considerable interval, for the idea was too novel to be digested all at once. But it was an age of unbridled license of imagination and of desperate courage. The mere possibility of encountering perils never until then conceived of was allurement enough, as, even to-day, our young adventurers go forth to die on the ice fields of the north and south poles, or in the mysterious heart of savage Africa, or on the ghastly plateaux of Tibet. In addition, there were the fabulous rewards that success seemed to promise.”
At first, though, if the plan of sailing west was even thought of, it would seem to have been regarded as less feasible than that of rounding Africa. Prince Henry, a son of King John I of Portugal—for it was the Portuguese, not the Spanish, who were the pioneers in this series of discoveries—determined to devote his life to the work. Retiring from the splendors of the Lisbon court, he built an astronomical observatory on the promontory of Sagres (in southern Portugal), extended its hospitalities to all the wise men of the age and sent out expedition after expedition to the south. “Until then,” says Dawson, “nautical knowledge was very meager. The compass served only to indicate direction, not distance or position, and did not suffice for the systematic navigation of the open Atlantic. The Portuguese first made that possible by using astronomical observations and inventing the quadrant and astrolabe.”
This knowledge, once acquired, was promptly applied. Madeira was discovered in 1418, the Canaries in 1427, the Azores in 1432. To the west the Portuguese ventured no farther, but, continuing south, they reached Cape Blanco in 1441, Senegambia and Cape Verde in 1445, the Cape Verde Islands in 1460, and the Gulf of Guinea in 1469. In 1471 they were the first Europeans to cross the equator. The idea was then conceived that they had only to keep on and they could round the southern extremity of the continent and reach Abyssinia and India by sea—a hope that was realized in 1487 when Bartholomew Dias arrived at last at the Cape of Good Hope. A few miles beyond, however, he was compelled by the condition of his crew to return and it remained for his compatriot Vasco da Gama some years later to double the cape and complete the voyage up the eastern coast and across the Indian Ocean to Hindustan.
II
The significance of these early voyages of the Portuguese lies in the fact that thereby it was demonstrated that a shorter route was needed—that with the very small and badly equipped vessels of the period the trip around the Cape of Good Hope, at least for commercial purposes, was impracticable; also in the fact that with Dias had sailed the Genoese navigator Bartholomew Columbus, a brother of the discoverer of America.
Years before that first great achievement, Christopher Columbus—who had studied at the University of Pavia and had himself taken part in one or more of Prince Henry’s African expeditions, and even ventured to the northwest, probably as far as Iceland—had been converted to the theory that the world was round and that the oceans west of Europe and east of Cathay were the same. As a consequence, he had concluded, the East Indies (as India, China, Japan, and the other countries and islands east of the Indian Ocean were indiscriminately called) could be reached from Europe by sailing west. Eighteen years before he was finally enabled to put this theory to the test, he had written Toscanelli, one of the foremost astronomers of the time, asking his opinion as to this possibility. Toscanelli sent him a copy of a letter he had written shortly before to King Alfonso of Portugal on the same subject, in which he said:
“I have formerly spoken of a shorter route to the places of spices than you are pursuing by Guinea. Although I am well aware that this can be proved by the spherical shape of the earth, in order to make the point clearer I have decided to exhibit that route by means of a sailing chart, made by my own hands, whereon are laid down your coasts and the islands from which you must begin to shape your course steadily westward, the places at which you are bound to arrive and how far from the pole or equator you ought to keep away.” (Neither in the chart nor in the description was there indication of anything whatever resembling the continents of North and South America.) “From the city of Lisbon as far as the very great and splendid city of Quinsay” (Pekin), he continued, “are twenty-six spaces, each of 250 miles. This space is about a third of the whole sphere. But from the Island of Antilia, which you know, to the very splendid Island of Cipango” (Japan) “there are ten spaces. So, through the unknown parts of the route, the stretches of sea are not great.”