Fig. 8.—Chart of the Mediterranean, 1500, by Juan de la Cosa.
But among maps of special regions the most notable are those known as Portolano maps, which were sailing charts accompanying the Portolani, or sailing directions for the Mediterranean Sea. These, no doubt, existed long before the Crusades, in connection with which they first come to our knowledge. They are in most respects remarkably accurate. They are distinguished by groups of rhumb-lines radiating from a series of centres, and marked usually with the initials of the names of the principal winds. As the accuracy of these maps was probably improved largely as the mariners’ compass came into use, it may be mentioned that the first European notice of the use of that instrument is provided by the English scientist Alexander Neckam (1157–1217) of St. Albans, foster brother to King Richard I. From his mention it appears by this time to have been a familiar object. The chief centres for the production of Portolano maps were naturally those identified in an important degree with over-sea commerce; such were Genoa, Venice, Ancona, and Majorca, while the seamen of Catalonia were also prominent at this period. These maps were in some cases extended to cover lands and seas beyond the immediate Mediterranean area, and even the whole world. World maps were usually circular with Jerusalem as a centre, and, in contrast to their accuracy in respect of the Mediterranean, they were not distinguished as a rule for much regard to the best sources of information, though for that we have already adduced some measure of excuse. The map of the world by Petrus Vesconte of Genoa (c. 1320) shows the Mediterranean and the Black Seas well, the Nile fairly, the Caspian indifferently, Scandinavia badly. A mountain range extends west and east across almost the whole of northern Europe and central Asia; rivers drain southward to the Black Sea from this; the Indian Ocean appears as a gulf; the south-eastward extension of the African coast is retained, and the peninsular form of India is not realized. Subsequent cartographers disagreed on such points as this last. Thus in a Florentine map of about 1350, called the Laurentian or Medicean Portolano, the west coast of India is well shown, and the influence of Marco Polo’s travels is to some degree apparent. This map, moreover, has other details of interest, such as the first appearance in any known map of the Azores and the islands of Madeira with their modern names. The Catalan map of 1375 recognizes the peninsular form of India for the first time, and Marco Polo’s results are shown to be thoroughly appreciated; and yet a century later the old errors as to the form of India and Ceylon persist even in a map so excellent in many directions as that of Fra Mauro (1457).
Chapter V.
PORTUGUESE EXPANSION AND THE REVIVAL OF PTOLEMY
There were obvious geographical and historical reasons why the kingdom of Portugal should furnish the important series of incidents in the expansion of geographical knowledge which now claims attention. The Arab power in the Iberian peninsula had been broken, and the Portuguese monarchy had established itself during the twelfth century. The Arab mantle of the explorer descended upon Portuguese shoulders. The small kingdom has a large extent of coastline; and not only is communication with Europe by land through the passes at either end of the Pyrenees comparatively difficult, but between those passes and Portugal were Spanish states, with which Portuguese relations were by no means amicable. Thus there was little opportunity for the commercial expansion of Portugal except over-seas.
The first important figure in the history of this expansion is that of Prince Henry, surnamed the Navigator (1394–1460), fifth son of King John I. His objects were to extend Portuguese commercial interests mainly in West Africa, and also, it would appear, to discover new lands, if they were to be discovered, to the west of those Atlantic islands which formed the limit of knowledge to the west from very early times. Even the knowledge of the islands themselves was indefinite enough; so that when, in or about 1415, Henry began sending his seamen to the Canaries and later to the Madeira and the Azores, he was inspiring, if not actual discovery, at any rate the acquisition of largely new information. Between 1415 and 1431 colonization and trade had already begun to be established in some of the islands; and, though the Portuguese navigators did not forestall Columbus, it is likely that they conceived the possibility of a westward route to the Far East. Prince Henry’s residence from 1438 to 1460 was Sagres, which consequently became a centre for geographical research, for he gathered about him expert cartographers and instructors for his navigators, whom he supplied with the best obtainable instruments, maps, and information: he used not only European but also Arab sources. With regard to the West African coast, he experienced some years of comparative failure; but from 1444 explorations here were rapidly extended, and a few of the leading navigators and explorers who worked under Prince Henry’s direction and after his death may be mentioned. In 1443 John Fernandez travelled inland in the district of Rio de Oro, and collected valuable information about the resources, physical conditions, and people of the south-west part of the Sahara. He made further journeys in 1446–47. Diogo Gomez, in 1448, made his way up the Gambia river. Alvise Cadamosto, a Venetian in Prince Henry’s service, was working in 1455 south of the Senegal; and in 1456 he visited, and probably actually discovered, the Cape Verde Islands. His accounts of his voyages were full and valuable, and he also dealt with the explorations of Pedro de Cintra, in 1461 or 1462, to Sierra Leone and the Gold Coast. Gomez made a voyage to the Cape Verde Islands in 1462; but he is most notable as chronicler of the life-work of Prince Henry.
King John II built on the prince’s foundations. In 1482 he sent out Diogo Cão, who discovered the Congo and ascended it for a short distance, and subsequently saw the coast of Angola as far as 13° 26´ S. at Cape Santa Maria. On a second voyage (1485–1486) he penetrated still further south, to Cape Cross. He erected pillars at various points on the coast—a practice followed by some of his successors; and some of these monuments have been found and preserved. In a voyage in 1486 or 1487–88 Bartolomeu Diaz extended the knowledge of the west coast nearly five degrees beyond Cão’s furthest, reaching 26° 38´ S. He was then driven south by high winds and storms, turned east, and found no land; he therefore steered north again, and struck the coast of what is now the Cape Province at Mossel Bay. Continuing eastward, he reached the Great Fish River, and was able to realize that the coast was now trending north-easterly, and that the southernmost point of the continent had been turned; but his crew were surfeited with their dangers, and insisted on returning. The important cape which he had discovered he is generally stated to have named Cabo Tormentoso, the Cape of Storms; and the story goes that King John, recognizing the importance of the discovery to the future object of a sea-route to the East, changed the name to the Cape of Good Hope. But there is good reason to believe that the happier name was given by Diaz himself. It had been one of the wishes of Prince Henry, and was one of the objects of the voyage of Diaz, to establish communication with a Christian king of whose powers rumours reached the west coast of Africa from the interior, and who was known under the name of Prester John. In 1487 Pedro or Pero de Covilhão and Alphonso Payva were sent, partly with the same object, by way of the Mediterranean. They visited Egypt, and after many wanderings came to Aden, whence Covilhão proceeded to Calicut and Goa in India, and, returning thence, travelled south along the East African coast as far as Sofala. He then journeyed in the coast lands of Arabia, and visited Mecca and Medina, and finally, entering Africa, proceeded to the court of Prester John in Abyssinia, where he was well treated, but from which he was never allowed to return home. Payva, meanwhile, had travelled into Ethiopia, and had died there.
The journey to India by way of the Cape of Good Hope was completed in due course in the last decade of the century; but earlier in that same decade the New World had been discovered by Columbus, and the era opened by these two tremendous incidents may be more fittingly considered in the following chapter; while for the moment some consideration may be given to the state of cartography and theory at the time when Columbus was planning his voyage.
The works of Ptolemy can have been known to few in the original Greek at this time, and for many centuries before. When, therefore, the translation of his Geography into Latin, originally undertaken by Emanuel Chrysoloras, a Byzantine scholar who settled in Italy, was completed in 1410 by his pupil Jacobus Angelus, these two students lit a beacon in the course of geographical study. The translation, which is usually identified with the name of Angelus alone, was issued under the title of Cosmography instead of Geography. It would appear that Angelus, of whose life apart from this work little is known, not only dealt with the text, but also did the maps into Latin. In a short time there was no lack of copies of the work, and it was soon found necessary to add to the maps at certain points where they failed to represent knowledge which was by this time in possession of the translators. Already about 1424 Claudius Clavus Swartha had constructed in Italy a map which showed the north-westward extension of knowledge as far as Greenland; the curious orderly curves by which the coastlines are represented frankly acknowledge the draughtsman’s lack of detail. About 1470 Nicolaus Germanus, often known erroneously as Donis, produced a manuscript edition of Ptolemy, with maps magnificently illuminated and on improved projections. He also added new maps, and it has been said of the collection that, as far as concerns methods of drawing, it is the prototype of all subsequent atlases (Nordenskjöld). An edition, probably of 1472, if not later, though it is dated earlier, reveals the use of a conical projection with meridians and parallels drawn across the maps; and, as points of some interest in comparison with modern maps, it may be added that the seas are green, the mountains blue, and other parts of the land red and yellow. The Florentine edition in verse, of about 1480, by Francesco Berlinghieri, contained an important series of new printed maps, including Italy, France, Spain, and Palestine.
Although the extension of knowledge to the north-west, as has been mentioned, attracted considerable attention on the part of the editors of Ptolemy, the recent Portuguese discoveries in West Africa did not, apparently, do the same. In an edition, for instance, of 1486, made at Ulm, a geographical description of the north-west lands, including Greenland, was furnished, and there were quoted the latitude and longitude of 183 places in northern Europe and Greenland; but there was no evidence that the conception of the southern limit of the habitable world by Ptolemy was understood to be now proved wholly erroneous by the Portuguese discoveries.