No. (23), of 1455, signed "Presbiter Bartolomeus de Pareto civis Janue ... composuit ... mcccclv. in Janua," is not of high value for its date, and shows no evidence of correspondence with Prince Henry's work. The West Africa of this design need not be specially noticed here.
No. (24), the most famous of the whole series, is more fully noticed on pp. cxl-cxliv. Fra Mauro was, perhaps, helped by Cadamosto among others. It is noteworthy that the Doge Foscarini, in the letter quoted below, pp. cxl-cxli, couples the success of Cadamosto and the work of Fra Mauro, as two things which should induce Prince Henry to persevere.[[268]]
A new mappemonde,[[269]] discovered by Kretschmer in the Vatican Library, and noticed in his monograph of 1891, is of 1448; while under date of 1444, Santarem refers to a "Portolan portugais inédit," which is not further known.
These were the works[[270]] which in cartography bore most closely upon the Infant's explorations; and we may here summarise the evidence of the same as to the advance of knowledge along the West African coast and among the Atlantic Islands.
At the beginning of the fourteenth century, as we have seen, there is no cartographical evidence of knowledge extending far beyond the Straits of Gibraltar—either down the mainland shore or among the Islands in the Ocean. But on Dulcert's Portolan of 1339, and on other productions of the same epoch, such as the Conosçimiento of about 1330, we meet with some of the Islands, and with the Continental coast as far as Bojador. Thus, in the Conosçimiento and the Laurentian Portolano of 1351, "the most important of the Azores, the Madeira group, and the Canary Islands, are denoted by the names they still bear," or by the prototypes of these names.[[271]] The same Medicean or Laurentian map of 1351, the Pizzigani of 1367-1373, the Catalan[[272]] of 1375, and others, "bear inscriptions even beyond C. Bojador"—inscriptions, however, which do not in their scattered and half-fabulous character give any decisive evidence of actual exploration to the south of this point before Henry's time.[[273]] Moreover, the shape of Africa in the "Atlante Mediceo" of 1351,[[274]] suggests—though it can hardly be said to prove—actual observations far beyond Cape Bojador made by the crews of storm-driven or India-seeking ships. But, after all, the map knowledge shown of Africa to the south of latitude 26° N. was so incomplete and so vague—perhaps even in the Laurentian Portolan the engrafting of a great theory on a tiny plant of fact—that the claim of first discovery in more southern regions cannot well be refused to Gil Eannes, Dinis Diaz, Cadamosto, and the other explorers of the Infant's school.
On the other hand, all the Atlantic groups, except the Cape Verdes and some of the Azores, were evidently known in whole or part to some of the fourteenth-century navigators and draughtsmen.
A good deal of hearsay knowledge about the interior of Africa is also indicated, as we have seen, in some of these maps, especially the Dulcert of 1339, and the Catalan of 1375; and in this connection we must refer to what has been said upon the trade-routes of North Africa; but these elaborate pictures of mountain ranges, Moslem kings, traders with their camels, and towns on eminences, have little more pretence to scientific accuracy than the Negro Nile of so many old geographers, which is probably a mistaken combination of the real but separate courses of the Benue, the Niger, and the Senegal.
Once more we have seen that the first two portolani plainly influenced by Prince Henry's discoveries are the Valsecca[[275]] of 1434-9 and the 1448 map of Andrea Bianco, drawn in London; and that the 1436 Bianco is probably a copy of a thirteenth-century work, showing no clear evidence of the new explorations. As to the Bianco of 1448, we may here add a word to what has been already said. On this example we find the west coast of Africa end suddenly with Cape Rosso, or Roxo, immediately south of Cape Verde, and "from this point the coast is drawn straight eastward in a style which indicates that the country beyond is unknown;" the "outline of this southern shore of Africa being delineated according to the maps of the Macrobius type." The work of 1448 is frequently copied in following years; as, for example, on several designs of Gratiosus Benincasa (1435 to 1482), wherein the west coast of Africa, from Ceuta to Cape Verde, "has the same contours and the same names."[[276]] All of these charts are believed by Nordenskjöld to be copies of the same Portuguese original. On the other hand, "Benincasa's Atlas of 1471 is widely divergent as regards the legends, and extends much further south.[[277]] It reproduces the discoveries along the coast down to Pedro de Sintra's voyage of 1462-3, and seems in part to be based on direct information from Cadamosto."[[278]]
Lastly, a more special notice must be taken of the great map of Fra Mauro, 1457-9.