Svat Soucek, "The Ottomans and Their Rivals, Galleys and Galleons, Portolan Charts and Isolarii," from his Piri Reis & Turkish Mapmaking After Columbus: The Khalili Portolan Atlas, Nour Foundation, 1995, pp. 10-33.


Turkey is a country blessed with long and beautiful coasts along three seas: the Mediterranean to the south, the Aegean to the west, and the Black Sea to the north. For several centuries, however, Turkey was the central part of a great and powerful state, the Ottoman Empire, and by the time this empire reached the peak of its might and extent during the reign of Sultan Suleyman the Magnificent (ruled: 1520 -66), its Mediterranean maritime frontier ran from the coasts of Albania and Greece to the Dardanelles, along the western and southern shores of Asia Minor and then by way of Syria, Palestine and Egypt to the province of Algiers in north-west Africa. Much of the Black Sea also came under Ottoman sway, as did the Red Sea. In southern Yemen the Turks acquired the great port of Aden on the Arabian Sea; and their conquest of Iraq gave them Basrah and the southern coast of the Persian Gulf.

Those were the days when Christendom both admired the Turk and trembled before him, for his armies were advancing ever closer to Europe's core. In 1521 they took Belgrade, in 15 26 Budapest, and in 1529 they laid siege to Vienna. Turkish fleets were eventually to launch equally spectacular campaigns in the Mediterranean, after having demonstrated their effectiveness early in Suleyman's reign at the conquest of Rhodes (1522). The naval build-up had started in the previous century,' and its first notable success occurred when Suleyman the Magnificent's great-grandfather, Mehmed the Conqueror (ruled: 1451-81), captured Constantinople in 1453. The conquest was in no small measure due to the war galleys he managed to introduce into the Golden Horn. Constantinople, which the Turks called Istanbul, became the empire's capital and eventually also its principal port and naval base. Mehmed the Conqueror used his navy again to assert Turkish supremacy over his two main maritime rivals, Venice and Genoa, in the Aegean and Black Seas, and by the time Suleyman the Magnificent took charge of the empire, the navy's range of operations covered the entire Mediterranean. Between 1533 and 1546 the Kaptan Pasha, or chief admiral, was Hayreddin Barbarossa (1470? - 1546), the greatest Turkish naval hero of all time, and the fleets under his command were the terror of the sultan's enemies and the hope of his friends.

Sultan Suleyman's most powerful adversary was Charles v of the Habsburg dynasty, who, as King of Spain from 1516 and as Holy Roman Emperor from 1519 to 1556, ruled a vast array of territories in Spain, the Netherlands, Germany and Italy as well as several islands in the western Mediterranean. Charles's lands did not border on Suleyman's as did those of his younger brother Ferdinand I, Archduke of Austria and from 1526 King of Bohemia and Hungary. At sea, however, there was a fife-long confrontation between two sovereigns, two religions, even two captains. The sultan in Turkey was the champion of Sunni Islam, and every victory he scored against Charles V earned him religious merit; the emperor in Spain was the defender of Catholic Christianity and was fired by a similar religious zeal. The symmetry extended into the two rulers' preoccupation with combating their heretical co- religionists: Suleyman the Shi'ites, Charles the Protestants. The two monarchs clashed repeatedly through their navies, during expeditions against each other's coasts and islands. In 1533 Barbarossa, a Turk from the island of Mytilene (Lesbos) who had conquered Algiers and become its first governor in 1519, was summoned by Suleyman to take charge of the Ottoman navy and undertake a number of official campaigns in the western Mediterranean; Charles V chose a Genoese nobleman and mariner, Andrea Doria (1466-1560), as his naval commander.

From a distance the confrontation might have appeared as a see-saw struggle between two ideologically incompatible rivals, with a slight edge held by the Turk. For throughout the two monarchs' lives the initiative and the offensive remained mostly on the Turkish side, without affording enough superiority to destroy the pponent. This would have been an increasingly distorted view, however, for only the Christian emperor saw the span of his realm reach beyond the oceans and ultimately acquire a vast dimension that encompassed the globe. This new dimension, absent from the Muslim ruler's mental horizon, may have gradually reduced the importance of the Mediterranean frontier in Charles V's eyes- and even more so in the eyes of his son Philip II.

The Mediterranean was the sea the Turks were familiar with and where they became the foremost naval power in Suleyman the Magnificent's time. Beyond the Strait of Gibraltar and the Suez isthmus, it was a different matter. The Turks felt less comfortable in the Indian Ocean, and the Atlantic lay below their horizon. By contrast, the ocean acted as a magnet to the maritime nations of western Europe, promising unprecedented opportunities once they had overcome their ancient fear of its vast expanse. It was the Portuguese who took the lead in this change of attitude after they acquired the port of Ceuta in Morocco in 1415 and started exploring that country's Atlantic coast. Prince Henry the Navigator (1394-1460) was the founder of a seafaring research centre at Sagres near Cape St Vincent and symbol of the methodical, government-sponsored advance southwards along the African coast. Trade, access to overseas resources and religious zeal motivated the Portuguese exploration. The riches of western Africa eventually confirmed their hopes: slaves, ivory, pepper and especially gold, traditionally traded northwards across the Sahara to Mediterranean ports, were now drawn to such ports as Elmina in Ghana, where they were bought by the Portuguese. For over half a century (c. 1480 -1540), Lisbon functioned as Europe's foremost point of entry for imported gold.

The explorers, meanwhile, had fixed their sights on a still more ambitious goal: discovering a sea route to the Orient and its riches, especially the spices for which there had been an insatiable appetite in the Near East and Europe since Classical antiquity. Grown chiefly in India and the East Indies, spices usually came to Europe in three stages: maritime merchants of the Indian Ocean brought them to the Red Sea or the Persian Gulf, local middlemen carried them to Mediterranean ports, and European merchants took them to their final destinations. In the later Middle Ages, Venice gained a virtual monopoly over this last leg of the spice traffic and cherished it as one of the chief sources of her wealth. The route made the products costly and their supply often unpredictable, because its first two stages were beyond the Europeans' control. People in western Europe began to search for direct maritime access to the sources of these goods. Their quest was reinforced by the spirit of adventure and curiosity characteristic of the Renaissance, but at first it was also driven by religious fanaticism bent on spreading Christianity among the heathen, finding the legendary Christian kingdom of Prester John in Africa or the Orient, and combating Islam, with the recovery of Jerusalem as the supreme goal.

Two maritime routes to the Orient were proposed: south around Africa and then north-east to India, or west across the Atlantic all the way to the Far East. It was not known whether either was possible until two memorable voyages in close sequence demonstrated, or seemed to demonstrate, the feasibility of both. In 1488 Bartolomeo Dias, the commander of yet another expedition sent by the King John II of Portugal (ruled: 1481-95), passed by a cape at the southern tip of Africa, which he called Cape of Storms but which his sovereign renamed Cape of Good Hope in recognition of the breakthrough this voyage represented in the quest for a sea route to India; and in 1492 Christopher Columbus, a Genoese in the service of King Ferdinand and Queen Isabella of Spain, accomplished what he thought was a voyage to the Far East by sailing west.

The two voyages were followed by others, and within a generation they led to the birth of Europe's first colonial empires, the Spanish empire in America and the Portuguese empire in Asia. The discoveries caused a sensation in Europe and were soon emulated, but the Turks and other Muslims, living in a different cultural and economic climate, felt no involvement in these events. Exploration of the earth and its oceans, desire for direct access to overseas sources and markets, curiosity about other places and peoples, even such questions as whether the sun was the centre of the universe and the re-examination of nature itself were all matters characteristic of Renaissance Europe but not of the contemporary Orient; and, last but not least, the invention and spread of printing in Europe created a new and important difference between its civilization and that of the Muslim world, where this innovation was banned until the beginning of the 18th century. The Orient felt superior to Europe culturally and spiritually, and perfectly satisfied with the existing structure of economic relations. Even on the religious level most Muslim countries had by then lost the conquering zeal of Islam's early centuries and accepted the status quo, in sharp contrast to the combined effect of crusading ideals and the success of the Reconquista, which gave the Iberian vanguard of Christendom its characteristic militancy. True, the Ottoman Turks, who had now assumed the religious leadership of the Muslim world, displayed as much commitment to the duty of the jihad, the Holy War, as their Arab predecessors. The sultans viewed the Balkans and Central Europe as their principal target, however, and they completely overlooked the offensive gradually being mounted around the globe by their opponents. It was Europe that strove consistently to find the route to the Orient, in fact to explore the real Orient and the rest of the unknown world. Initiatives from the Orient were few, and they seldom fared well. This fact alone makes them the more interesting and important. One such initiative was that of Piri Reis, an Ottoman Turkish mariner, cartographer and geographer, the main theme of this study.


No essay on Piri Reis could be considered complete without a few words on the ships of the time because of the variety he and others mentioned in their works and depicted on their charts. The most frequently mentioned and commonly used type is a vessel he calls the kadirga, a Turkish word of Greek origin meaning galley. A long, low, narrow ship of shallow draught, the galley was propelled by oars when entering or leaving harbours, when pursuing or fleeing an enemy, or in battle. In normal cruising conditions, however, it relied mainly - unless becalmed - on one or two lateen (triangular) sails. An average galley in Piri Reis's time had between 24 and 26 oar-benches, or thwarts, on each side. There were smaller and larger versions. One of the former, called kalita in Turkish and probably corresponding to the Italian galiotta or fusta, was a ship favoured by corsairs for its speed and its ability to operate in difficult circumstances, penetrating shallow anchorages, hiding in coves, suddenly pouncing on its prey or withdrawing into havens that were inaccessible to others. Versions larger than the standard type were rare among the Turks but commonplace among their longest-standing rivals and neighbours, the Venetians. One type was the bastarda, a term applied in Turkish to the special galley used by the commander of an Ottoman fleet. The word is seldom used by Piri Reis, because his work on navigation in the Mediterranean, the Kitab-i Bahriye ('Book of Seacraft'), pays attention chiefly to the 'civilian', commercial aspect of seaborne traffic. He frequently mentions the mavna, the largest type of merchant galley, known in Italian as galera grossa di mercato ('large merchant galley'). This was the standard ship of the republic's convoys, bringing such valuable cargo as pepper or silk from Alexandria and other Levantine ports to Venice. Passenger traffic taking Christian pilgrims to the Holy Land also mostly used galleys.

The galley and its variants, especially the smaller ones, had a long history in the Mediterranean. Greek legend has Jason sail in a galley in quest of the Golden Fleece, while Homer portrays Odysseus and his companions sailing in one, on occasion practising piracy. Classical fleets used galleys in their battles, as did those of the Byzantines and Arabs when they fought in the early centuries of Islam or when they preyed on each other as corsairs. The Saracens terrorized the Christian part of the western Mediterranean in a similar manner, as did the Catalans the Muslim part of the eastern half, where they raided some of the prosperous Egyptian towns, such as Tinnis, out of existence. And it was with their kadirgas and kalitas that the Barbarossa brothers completed what Kemal Reis and Piri Reis had shown to be possible, the Turkish conquest of North Africa and its rescue from the Spanish Reconquista.

The galley family, then, were ships of war and piracy rather than of freight and trade. But there were numerous and important exceptions - the large Venetian merchant galleys, for example - and the definition needs serious qualification. Broadly speaking, galleys and their relatives belonged to the category of 'long ships', whereas pure sailing ships belonged to that of 'round ships', which were not entirely round, of course, but were so called because they had a wider beam and taller freeboard than long ships. The term 'round ship' is used mainly in the context of the later Middle Ages, when sailing ships began to grow taller and more massive, notably the ever-larger merchantmen of the Italian republics. Oarless, purely sail-driven ships also had an age-old Mediterranean lineage, having been the standard vessels of Greek and Phoenician traders.' Economics was the main reason for their popularity in Classical times, as It was in the Middle Ages: instead of feeding and carrying a large number of rowers, an expensive proposition, more cargo could be added; and, unlike prisoners of war, slaves and convicts, of whom rowing crews were often composed, a cargo presented no security risk. But all sailing ships depended on the whims of the wind, which could play a critical role in moments of emergency. It was the greater mobility of the galley that weighed in its favour as a vessel of war and piracy; and the corsairs often turned the burden of rowing crews to their advantage, for the rowers were comrades-in-arms who could join the battle if necessary. An analogy with the Vikings and their ships immediately comes to mind.

Unlike the 'Frankish' galea and the Turkish kadirga, there is no distinctive term for the purely sail-driven ship of Piri Reis's time. In the Romance languages of the Mediterranean and Atlantic seaboards, people simply used the generic word for ship, based on the Latin navis: nave, nao, nau or nef. This imprecise generic usage could be sufficient if the vessel was a large merchantman of the exclusively sail-driven type, but specific terms were used for a vessel with special characteristics, such as the carrack or caravel. In Turkish the generic term for ship, gemi, was not used to distinguish sail-driven vessels from oar-driven craft; specific terms were used for the former, such as barca, koke, karaka or kalyon. These were all words borrowed from the lingua franca, and they frequentlyappear in the Kitab-i Bahriye of Piri Reis. Barca, derived from the Venetian barza, is the word most often encountered; it referred to the massive, tall, square-rigged merchantman that Venetians and other traders used for hauling heavier, bulkier, less costly cargo than spices, silk or precious stones. Such ships, no doubt fairer game than the large merchant galleys bristling with defenders, were a frequent prize of the Turkish gazis, who usually sold them and their cargoes but sometimes - probably not for long included them in their fleets. In the first version of the Kitab-i Bahirye Piri Reis relates how the Turkish gazis approached the Algerian port of Bijayah with such a barca, as one of their three ships. But Piri Reis's use of the term suggests that he is often simply referring to any sail-driven merchantman, regardless of its size or specific characteristics, a usage akin to that of the words derived from navis in Romance languages. It seems that the word barca, acquired this generic connotation in Ottoman Turkish, especially in the form parca.

When Piri Reis wants to emphasize that he has a very large type of merchantman in mind, he uses the term karaka. Known in English as carrack, this was the largest sailing ship of his time, a massive vessel developed by the Genoese which instantly captured any Observer's eye with its high superstructures of forecastle and sterncastle. It was taken over by the Portuguese once they had launched their Carreira da India -- the regular sailings of their fleets to the Orient. The carrack was square-rigged like most large merchantmen, but with one and eventually two additional lateen sails on the mizzen-masts that gave it greater manoeuvrability. Piri Reis never mentions carracks owned by Turks; they were ships of long-distance trade and eventually of oceanic voyages, and the Turks shied away from both.

As for Piri Reis's koke and kaylon, they illustrate the shifting nature of maritime terminology. The former is a loan- word derived from the Italian cocca, which in turn is an adaptation of the German kogge, the single-masted square- rigger of the Hanseatic League's North Sea fleets. Italian shipbuilders emulated and eventually transformed the Hanseatic kogge into their barzas and carracas. The term cocca was waning in Italian by the time of Piri Reis, who himself uses the word koke only seldom, and then with the general meaning of a large vessel used by the infidels; on the map of 1513, moreover, both barca and koke are used as synonyms for karaka.

The kalyon, on the other hand, was to know its days of glory only after Piri Reis's time. The equivalent of the galeone or galeon (literally, 'large galley') in Romance languages, and of galleon in English, kaylon appears in the Kitab-i Bahriye to denote a merchant vessel used chiefly by Christians and more or less synonymous with a smaller kind of barca. Our author could not have foreseen that, two generations later, Spanish and English galleons would grow into great oceanic sailing ships built and equipped both as freighters and men-of-war; for by then these vessels, partly a development of the carrack on the one hand and of the galley on the other, had elongated hulls studded with cannons, and confronted each other in battles that were totally different from those traditionally fought in the Mediterranean.

Finally, three more vessels current in the Kitab-i Bahriye deserve mention: igribar, kayik and sandal. The igribar, the Turkish form of the Greek griparion, appears to have been a relatively small, one-masted type of sail-driven merchant vessel routinely used for coastal shipping in Turkish home waters. The kayik, besides the generic gemi, is the only term under discussion that has a genuinely Turkish etymology. It was a small vessel equipped with oars and a sail, similar to one of the lesser versions of the galley. In the Ottoman fleet its role appears to have been mainly to provide logistical support, but Piri Reis applies it also to boats used by local privateers along Turkey's Aegean coast. In later times the term was also applied to merchant vessels plying the eastern Mediterranean between Egypt and Istanbul. With the sandal we return to the common Mediterranean heritage, for the term goes back to the Byzantine Greek sandalion. It was a rowing boat small enough to be carried on board or to be towed. There are innumerable references to the sandal in the Kitab-i Bahriye, and its most typical function was carrying a scouting party ashore to get fresh water or perform some other duty.

A term hardly used in the Kitab-i Bahriye - perhaps only once - is karavele; on the other hand, the word and the vessel it depicts appear several times on both of Piri Reis's world maps. This was the caravel, a vessel the Portuguese and Spaniards favoured for their voyages of exploration and discovery. A fight, nimble ship with two or three masts, itwas at least partly lateen-rigged and thus able to sail close to the wind, yet it was frequently re-rigged with square sails for cruising before a steady wind. The caravel could operate in a broad range of situations and was well suited to exploring unfamiliar coasts or entering river estuaries, while also being able to cover any distance. Although it probably combined elements drawn from the shipbuilding traditions of the Mediterranean and the Red Sea or the Indian Ocean - and was thus partly Arab in origin the triumph of the caravel began when Henry the Navigator launched the great exploration of Africa's Atlantic coasts and adjacent waters. Columbus called two of the three ships with which he sailed on his first voyage carabelas (the Pinta and the Nina; the flagship, the Santa Maria, was a nao), and one of the three ships with which Vasco da Gama reached India in 1498 is also believed to have been a caravel. Once the routes were established and regular sailings started, however, the larger nao passed to the fore: in the form of the carrack, as we have seen, it became the standard ship on the Portuguese Carreira da India. The galleon was destined to play a similar role in the Spanish silver fleets of the Atlantic and on the Manila run between Mexico and the Philippines, and eventually to become the English 'ship of the line', the battleship with which England began to emerge as the dominant sea power.

The galley is absent from Piri Reis's world maps, and from any discussion of oceanic exploration and voyages. Indeed, a parallel might be drawn between the galley and the portolan chart: both were an essentially Mediterranean, phenomenon, and both were used on the oceans for brief periods and with no long-term effect. The galley could not match the caravel or other types of sailing ships in seaworthiness - a critical factor on the oceans. And its fighting force, primarily of an infantry character, was that of the past and had little chance of succeeding against the carracks and galleons, ever more heavily armed with artillery. This disparity, which was to play a role in the confrontation between the Ottomans and the Portuguese in the Indian Ocean, is also illustrated by the change in circumstances that took place in the 17 years between the battle of Lepanto in 1571 and the English fleet's defeat of the Spanish Armada in 1588. Lepanto was a combat between the troops of two galley fleets, and, despite the initial cannonade from Don John of Austria's six famous galleasses, it was close in character to the naval encounters of the Greeks and Persians in the 5 th century BC, whereas the manoeuvre-and-artillery duel between the Spanish and English galleons in 1588 was more akin to the contests between British and German warships in the First World War.

Of the various features with which Piri Reis adorned his map Of 1513, the carracks and caravels most readily catch the eye. Ships and boats also appear on the charts of most manuscripts of the second version of the Kitab-i Bahriye: sailing vessels Piri Reis would have called barcas, galleys, kayiks and sandals. In certain cases attempts were made to be explicit: in one manuscript the lagoon of Venice - whose canals are studded with gondolas - is alive with vessels identified as passenger kayiks and water-hauling sandals; a kaylon is approaching the Rialto bridge, while two carracks, too large to enter the lagoon, he outside the entrance. An altogether special case is the chart of the Nile at the level of Cairo. Piri Reis must have been fascinated by the various boats he saw on the river, for he included drawings of four types, all of them known by name from Arabic sources: jarim, 'aqabah, qiyasah and shahtur. This instance of four types of vessel being both named and drawn by a contemporary witness may well be unique.

Two other Turkish manuscripts depicting ships deserve mention, the History of the Conquest of Siklos, Esztergom and Szekesfehervar, also known by the less unwieldy title of the Suleymanname, and the Shahnamah of Selim Khan.

The former consists of a text and illustrations by Matrakci Nasuh, a janissary who later became a chronicler and court artist and is better known for his illustrated account of Sultan Suleyman's Iraq campaign of 1534-5. The Suleymanname describes the twopronged campaign Of 1543 against the Habsburgs: the land war in Hungary led by the sultan himself, and, on folios 16b-36a, the sailing of the Ottoman fleet under Hayreddin Barbarossa to the western Mediterranean, where France was Turkey's ally. The fleet is shown calling at or making naval demonstrations before the ports of Reggio, Antibes, Toulon, Marseilles, Nice and Genoa and off an unspecified coast. Matrakci Nasuh depicted these places as if seen from an elevated position offshore - a similar perspective is used in later manuscripts of the Kitab-i Bahriye - and usually with part of the fleet either anchored in the harbour, as in the case of Marseilles, or sailing by information, as before Genoa. The ships, elegantly drawn, are mostly galleys.

The Shahnamah of Selim Khan, produced in 1581, was written by Lokman, while its paintings are believed to be by the court painter Osman, an artist who illustrated many other manuscripts produced at the Ottoman court at this time. This 'Shahnamah' intended to glorify some of the achievements of the reign of Suleyman's successor, Sultan Selim II (ruled: 1566-74), and it includes episodes from a confrontation between the Ottomans and Venetians at Navarino in 1572 and from the siege of La Goulette (Halq al-Wadi), a prelude to the recapture of Tunis in 1574. Folio129a shows the infidels precipitately leaving the shore at Navarino in an effort to reach a galley lying close inshore; only the ship's stern is depicted but with all the paraphernalia - flag, pennants, lanterns and the end of the row of oars. On the facing page, folio 128b, we see one Ottoman galley displayed in full and the stern of another. The scene from the siege of La Goulette on folios 145b-146a appears to show the fortress moments after the resistance of the Spanish garrison has collapsed. Again the place is shown from above, from a position somewhere in the Gulf of Tunis, where we see four galleys and the stern of a tall sailing ship. Had the artist placed a full view of the latter in the midst of the galley fleet, his miniature might have been more eloquent still.


When Piri Reis went to sea some time in the late 1480s, his uncle or other companions must have introduced him to the navigational tools they were using. Besides the memory and experience of the men themselves, the most useful of these were nautical charts, texts on sailing and the compass. The charts and texts would not have been in Turkish, but in the Romance idioms of the principal Mediterranean seafarers of the time, the Italians and Catalans. Carta portolana or portolano were the usual terms for such charts, and the texts themselves were also often called portolani, for both were tools of the 'haven-finding art'. (The term compasso was also sometimes applied to such charts and texts as well as to the instrument.) Modern historians use the terms 'portolan' and 'portolan chart' rather than simply calling them nautical charts and sailing directions because of their special character.' When they first appeared in the 13th century they differed from any tools of similar purpose made earlier, and they also differed markedly from those that were introduced in the early modern period with the advent of celestial navigation. Moreover, they had a very specific geographical focus, the Mediterranean.

It was the spread of the compass that assisted the creation of the portolan as a new type of nautical chart in the 13th century, and it was the growing role of improved instruments of celestial navigation, coupled with the different demands of the rapidly expanding oceanic voyages, that made it obsolete several centuries later. The introduction of the magnetic needle into the Mediterranean (the earliest record is from 1187) made it possible for pilots to plot their courses more precisely according to the points of compass and allowed them to grasp much more accurately the contours of the two seas they most frequently sailed, the Mediterranean and the Black Sea. Thus the portolan chart was a revolutionary innovation compared to earlier maps of the area or to contemporary land maps that did not take the development of the portolan into account. The most characteristic feature of the portolan chart was the network of thumb fines indicating the points of the compass and facilitating the plotting of the ship's course. These lines radiate from several focal points arranged concentrically around a central point which was later often embellished with elaborate windroses, as were some of those on the periphery. The second most important feature of portolan charts was the scale bar, which provided an improved method of measuring the distance from one place to another. Both features later proved inadequate in the face of competition from nautical charts created with instruments of celestial navigation. Mariners of the Atlantic Ocean eventually abandoned the meshes of thumb lines showing the compass points or 'winds' on their charts, and replaced them with grids of parallels and meridians showing latitude and longitude; the windrose was preserved as a necessary component. Determining the ship's position in terms of latitude, vital for navigation over the vast expanses of the world's oceans, had not been needed in the relatively small and enclosed Mediterranean. (Significantly, neither the curvature of the earth nor magnetic variation was taken into account in the latter case.) Once Atlantic mariners began to dominate the art of seafaring, the portolan chart had to give way. This did not happen overnight, for the portolan chart was used in the Atlantic in the 15 th century and spread over the world's oceans in the 16th, 6th, being the type adopted and given a new dimension by the earliest discoverers themselves, with the Portuguese far in the vanguard. The transition to charts also indicating latitude and longitude and grappling with the problem of projection eventually got under way, but a significant number of world maps from the Age of Discovery were portolan charts in style: Piri Reis's two maps are outstanding examples of this group.

The classic portolan chart focused on the Mediterranean, however. Sometimes it also covered the Black Sea or the Atlantic coast of Europe, including the British Isles, north-west Africa or both, the range of operations of medieval Mediterranean seafarers. Its physical dimensions tended to be limited to that of a sheepskin, for such charts were most frequently drawn on parchment. By the turn of the 16th century, two, three or even more such skins were combined to make world maps of the portolan type. This was the case with Piri Reis's famous Map of1513 and probably also with the map of 1528, although only parts have survived in both cases (one half or one third of the former and one sixth of the latter).

Other features that set the classic portolan chart apart are worth noting. One is the relative comprehensiveness and consistency of scale: they cover the entire Mediterranean or a large segment of it, such as its western or central or eastern part, or the Adriatic or the Aegean; the scale remains basically the same even when the chart has been cut up and assembled in an atlas. In other words, there are no known large-scale portolan charts of a small area, as is standard in modern nautical cartography. Another distinctive feature is that the names of harbours and other coastal features are usually written in a close sequence at right angles to the coast but 'inland', so as to leave room on the water side to record the location of shoals (by means of minute dots), submerged rocks (by means of little crosses) or islands. The small scale of a typical chart means that the names crowd its coastal contours in a continuous row, while the interior of the land mass is empty, as it is on modern nautical charts. The colour of the ink also played a role. It is mostly black, but the more important cities are in red. Black was used for the rhumb fines of the eight principal points of the compass, or, to use the mariner's parlance, the eight 'winds' (north, north-east, east, south- east etc.); green for the next subdivision, the eight 'half-winds' (north-north-east, east-north-east, east-south-east, south-southeast etc.); and red for the last subdivision, the eight 'quarter-winds' (north-by-east, north-east-by-north, north-east-by-east, east-by-north etc.) - 32 points of the compass in all. Some of these features may appear decorative to us, and most portolan charts are indeed pleasing to the eye, but the function of colour is beyond doubt: the pilot could more easily spot an important port written in red ink or recognize that the rhumb line leading to a specific location indicated west-south-west when drawn in green.

It was the Italians and Catalans who had created the portolan chart by the beginning of the 13 th century, and they continued producing the greatest number of charts until the demise of the genre in the 17th century. There eventually appeared groups of well known cartographers or workshops founded by them. A brilliant example is the workshop of Abraham Cresques, a Jewish cartographer of Majorca who was succeeded in this profession by his son Jefuda. By 1375 Abraham Cresques had drawn a beautiful mappamundi of 12 folding leaves that is customarily called the Catalan Atlas. It is an amalgam of three principal traditions: it follows earlier medieval concepts in making Jerusalem the geographical centre of the world; information derived from recent travels such as those of Marco Polo or of Arab sources - possibly Ibn Battutah - were used for the interiors of Asia and Africa; and the portolan genre is evident in the depiction of the Mediterranean and adjacent areas and in the mesh of rhumb lines.

As for the makers of portolans in the stricter sense of the word, the craftsmen were often former mariners. One such sailor-turned-mapmaker was the Venetian Andrea Bianco, remembered for an atlas he made in 1436 and for a remarkable chart he drew in 1448 . Grazioso Benincasa, a native of Ancona but active also in Venice, Genoa and Rome between 1461 and 1482, was among the most prolific of the strictly professional craftsmen . Another Anconese, Conte Hectornano Freducci, lived a generation later and was thus a contemporary of Piri Reis; Freducci's earliest chart dates from 1497, and he made an atlas as late as 1537. Some of these chart-makers, such as Bianco and Benincasa, took note of Portuguese exploration along the coast of western Africa, and their charts document its progress. By Piri Reis's time, the Portuguese began to take the lead in oceanic cartography, and the achievements of 16th-century Portuguese cartographers present a fitting counterpart to their nation's voyages of exploration and to the work of a remarkable group of contemporary historians and poets who recorded them.

Maps in general have an intrinsic aesthetic appeal, and portolans often reached the level of an exquisite minor art. The higher the aesthetic level of a portolan chart, however, the less likely it was that it was actually used on board ship; more probably, these presentation' charts were produced for important or wealthy customers. Sailors contented themselves with plainer examples, most of which have not survived. One of the distinguishing features of 'presentation' portolan charts is that the interior of the land mass is no longer blank but frequently displays such features as cities, rulers or other persons worthy of attention, animals, birds, rivers, mountains and so forth; flags often indicate the political allegiance of a place. With the spread of the portolan chart to the oceans and newly discovered or explored territories, brief texts were added to tell the story of a voyage or of the quaint creatures or plants or other novelties found there. Piri Reis's world map of 1513 eloquently displays most of these elements.

Mariners of Christian Europe - the Italians and Catalans - were the creators and principal producers and users of portolans within the Mediterranean, yet the Muslims Arabs and Turks - controlled one half of the Mediterranean coastline, and one of the best contemporary definitions of what portolan charts were and who used them is by an Arab author, the great Tunisian historian Ibn Khaldun (d. 1406):

Ibn Khaldun's perceptive account stops short of giving us one vital piece of information: how great was the share of Muslims in the production and use of portolan charts? An inventory of known portolans made by the time Piri Reis joined the profession speaks for itself. 180 made by Christians as against three Arab and no Turkish specimens. One contributing factor may have been the predominance of Christians in long-distance commercial shipping and passenger traffic. The oldest example is the socalled Maghrib Chart in the Biblioteca Ambrosiana, Milan. Anonymous and undated, it covers the western Mediterranean and is believed to have been drawn in the first half of the 14th century. The other two Arab portolan charts date from the 15 th century, and their authors' names also suggest a Maghribi origin: the first, now in the Topkapi Palace Library in Istanbul, was prepared by Ibrahim al-Katibi al-Tunusi ('of Tunis') in AH 816 (AD 1413-14) and covers the entire Mediterranean; the colophon of the second, which covers both the Mediterranean and the Black Sea and is now in the Maritime Museum in Istanbul, records that it was drawn by Ibrahim al-Mursi ('of Murcia') at Tripoli in AH 865 (AD 1461). No comparable Arab charts of the Mediterranean are known from subsequent periods; the quaint maps and atlases produced by the dynasty of Tunisian cartographers known by their nisbah of Safaqusi ('of Sfax') in the 16th and 17th centuries are an amalgum of the portolan tradition with other cartographic methods going back to al-Idrisi in the 12th century and could hardly have reflected actual practice. On the Turkish side, Piri Reis's works dominate this period, but three other atlases of portolan charts of the standard Mediterranean type have survived: the Atlas of Ali Macar Reis, which is preserved in the Topkapi Palace Library, the so-called Atlas-i Humayun ('imperial atlas'), recently discovered by Thomas D. Goodrich in the Archaeological Museum in Istanbul," and the Deniz Atlasi ('sea atlas'), which the same scholar found in the Walters Art Gallery in Baltimore. They all pertain to the second half of the 16th century, and, with the more refined copies of the Kitab-i Bahirye, they reflect the vogue this genre must have enjoyed among the more sophisticated Ottomans. The plainer, functional marine charts or atlases that no doubt existed have not survived, except for such isolated examples as the Aegean sea-chart of Mehmed Reis ibn Menemenli.

Portolan charts and the texts that accompanied them were two faces of the same coin. The text must have been equally indispensable to the mariner, for it complemented the chart by focusing on features and details better suited to verbal description: the position and quality of harbours and anchorages, their landmarks when approached from the sea, ships' lanes and difficult passages, the availability of fresh water, even the human and political situation in a port or area. Some of these data make the portolan text more part of the seafaring literature which began in Antiquity with Greek periploi and stadiasmoi and continues today with constantly updated sailing directions. At the same time, the texts reflect the three main stages of navigational technique: the pre- compass stage of Antiquity (directions but no compass bearings); the compass stage of the later Middle Ages (bearings and distances but no latitude and longitude); and the latitude and longitude stage of the modern era.

The three phases are made palpable by the different cartographic forms used. Virtually no charts have survived from the periplous period of Classical antiquity, no doubt because those that may have existed were too rudimentary or too marginal to have been produced in any quantity. The portolan charts of the second stage held sway for some four centuries and are perhaps the most distinctive cartographic type ever, while the third phase is represented by the modern nautical chart. The decorative glamour that has always surrounded the more elaborate maps reached its climax with the portolan genre, for it is these which drew the attention of the contemporary elite and continue to draw that of collectors and scholars. The texts, on the other hand, have always remained the charts' poor relations, for they were read only by sailors. There are no renowned authors of portolan texts and no contemporary or modern collectors, and without the conscientious archivist of the past and the scholar of the present, who find them to be welcome historical sources, they would have been doomed to oblivion. Piri Reis's works confirm this contrast but qualify it in a special manner.

Any discussion of the portolan genre, but especially an analysis of Piri Reis's Kitab-i Bahirye, would be incomplete if it failed to mention the related genre of the isolario. This was a combination of text and maps describing various islands. In contrast to portolan texts, those of the isolarii focused on the topical and historical aspects of a given island and paid only marginal attention to navigational matters, for their purpose was not to help the mariner but to amuse and instruct the curious reader. The maps lack the networks of rhumb lines characteristic of portolan charts, but there is a greater wealth of detail pertaining to the interior. However, they betray a strong fink with portolan charts in that they usually retain a rudimentary windrose with the eight principal winds, and in their contours and style, which are those of the portolan charts but on a larger scale. The craftsman making an isolario map drew an enlarged rendition of a model he found on a portolan chart.

The genesis of this delightful genre occurred in 1420 when the Florentine priest Cristoforo Buondelmonti, who had lived in Rhodes and travelled in the Aegean and Ionian archipelagos between 1406 and 1419, presented his Liber insularum archipelago to Cardinal Orsini of Florence. The autograph does not seem to have survived, but there are several copies, one from 1429, and there is even a contemporary Greek translation. Another indication of the book's success is the fact that other authors have shamelessly pillaged it. Buondelmonti's isolario consists of 79 chapters and 36 maps, the islands ranging from Rhodes to Crete and Corfu. The author made two sidesteps to the mainland by including descriptions of Gallipoli and Constantinople, which is also depicted in a topographic view. His idea caught on, and other people compiled isolarii. In 1477 the first printed specimen, the isolario of Bartolommeo da li Sonnetti, appeared. is also limited itself to the Aegean Sea, but by the 16th century other authors were producing isolarii that described islands in the Mediterranean and even in other parts of the The Libro ... de tutte l'isole del mondo of Benedetto Bordone, published in Venice in 1528, and Tommaso Porcacchi's L'isole piu famose del mondo, published in the same city in 1572, are the best known examples. The division of the subject matter into chapters, the provision of the chapters with maps and the emphasis on the historical aspects of each place set the isolario genre apart from that of the portolan. Some of these characteristics are present in the Kitab-i Bahriye, however, and the isolario's influence on the Turkish work is certain both in its conception and in a number of specific details.