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rabic science constitutes one of the main links between the older learned world of the Greeks and Latins and the Europe of Henry the Navigator and of the Renaissance. In geography it adopted in the main the results of Ptolemy and Strabo; and many of the Moslem travellers and writers gained some additional hints from Indian, Persian, and Chinese knowledge; but, however much of fact they added to Greek cartography, they did not venture to correct its postulates.

And what were these postulates? In part, they were the assumptions of modern draughtsmen, but in some important details they differed. And first, as to agreement. Three continents, Europe, Asia, and Africa, an encircling ocean, the Mediterranean, the Black Sea and Caspian, the Red Sea and Persian Gulf, the South Asiatic, and North and West European coasts were indicated with more or less precision in the science of the Antonines and even of Hannibal's age. Similarly, the Nile and Danube, Euphrates and Tigris, Indus and Ganges, Jaxartes and Oxus, Rhine and Ebro, Don and Volga, with the chief mountain ranges of Europe and Western Asia, find themselves pretty much in their right places in Strabo's description, and are still better placed in the great chart of Ptolemy. The countries and nations from China to Spain are arranged in the order of modern knowledge. But the differences were fundamental also. Never was there a clearer outrunning of knowledge by theory, science by conjecture, than in Ptolemy's scheme of the world (c. a.d. 130). His chief predecessors, Eratosthenes and Strabo, had left much blank space in their charts, and had made many mistakes in detail, but they had caught the main features of the Old World with fair accuracy. Ptolemy, in trying to fill up what he did not know from his inner consciousness, evolved a parody of those features. His map, from its intricate falsehood, backed as it was by the greatest name in geographical science, paralysed all real enlargement of knowledge till men began to question, not only his facts, but his theories. And as all modern science, in fact, followed the progress of world-knowledge, or "geography," we may see how important it was for this revolution to take place, for Ptolemy to be dethroned.

THE WORLD ACCORDING TO PTOLEMY.

(see list of maps)

The Arabs, commanding most of the centres of ancient learning (Ptolemy's own Alexandria above all), riveted the pseudo-science of their predecessors on the learned world, along with the genuine knowledge which they handed down from the Greeks. In many details they corrected and amplified the Greek results. But most of their geographical theories were mere reproductions of Ptolemy's, and to his mistakes they added wilder though less important confusions or inventions of their own. The result of all this, by the tenth century a.d., was a geography, based not on knowledge, but on ideas of symmetry. It was a scheme fit for the Arabian Nights.

And how did Ptolemy lend himself to this?

His chief mistakes were only two;—but they were mistakes from which at any rate Strabo and most of the Greek geographers are free. He made the Indian Ocean an inland sea, and he filled up the Southern Hemisphere with Africa, or the unknown Antarctic land in which he extended Africa.[8] The Dark Continent, in his map, ran out on the one side to the south-east of China, and on the other to the indefinite west, though there was here no hint of America or an Atlantic continent. It was a triumph of learned imagination over humdrum research. Science under Hadrian was ambitious to have its world settled and known; it was not yet settled or fully known; and so a great student constructed a mélange of fact and fancy mainly based on a guess-work of imaginary astronomical reckonings. On the far east, Ptolemy joined China and Africa; and on this imaginary western coast, fronting Malacca and Further India, he placed various gratuitous towns and rivers. Coming to smaller matters, he cut away the whole of the Indian peninsula proper, though preserving the Further or "Golden" Chersonesus of the Malays, and he enlarged Taprobane, or Ceylon, to double the size of Asia Minor. Thus the southern coast of Asia from Arabia to the Ganges ran almost due east, with a strait of sea coming through the modern Carnatic, between the continent and the Great Spice Island, which included most of the Deccan. The Persian Gulf, much greater on this map than the Black Sea, was made equal in length and breadth; the shape of the Caspian was, so to say, turned inside out and its length given as from east to west, instead of from north to south; while the coast line, even of the familiar Euxine, Ægean, and Southern Mediterranean, was anything but true. Scandinavia was an island smaller than Ireland; Scotland represented a great eastern bend of Britain, with the Shetlands and Färoes (Thule) lying a short distance to the north, but on the left-hand side of the great island. The Sea of Azov, hardly inferior to the Euxine, stretched north half way across Russia. All Central Africa and the great Southern or Antarctic continent was described as pathless desert—"a land uninhabitable from the heat"; and the sources of the Nile were accounted for by the marshes and Mountains of the Moon.

Thus all the problems of ancient geography were explained: where Ptolemy's knowledge failed him altogether, no Western of that time had ever been, or was likely to go. The whole realised and unrealised world was described with such clearness and consistency, men thought, that what was lacking in Aristotle was now supplied.

Yet it is worth while observing how, centuries before Ptolemy, in the ages nearer to Aristotle himself, the geography of Eratosthenes and Strabo, by a more balanced use of knowledge and by a greater restraint of fancy, had composed a far more reliable chart.[9]

This earlier and discredited map avoided all the more serious perversions of Ptolemy. Africa was cut off at the limit of actual knowledge, about Cape Non on the west and Cape Guardafui on the east; and the "Cinnamon-bearing Coast," between these points, was fringed by the Mountains of Æthiopia, where the Nile rose. This was the theory which revived on the decline of the Ptolemaic, and which encouraged the Portuguese sailors with hopes of a quick approach to India round Africa, as the great eastern bend of the Guinea coast seemed to suggest. Further, on this pre-Ptolemaic map the Southern Ocean was left untouched by a supposed Southern Continent, and except for an undue shrinkage of the Old World in general as an island in the midst of the vast surrounding ocean, a reliable description of Western Asia and Central Europe and North Africa was in the hands of the learned world two hundred years before Christ.

It is true that Strabo's China is cramped and cut short; that his Ceylon (Taprobane) is even larger than Ptolemy's; that Ireland (Ierne) appears to the north of Britain; and that the Caspian joins the North Sea by a long and narrow channel; but the true shape of India, of the Persian Gulf and the Euxine, of the Sea of Azov and the Mediterranean, is marked rightly enough in general outline. This earlier chart has not the elaborate completeness of Ptolemy's, but it is free from his enormous errors, and it has all the advantage of science, however imperfect, over brilliant guessing.

Of course, even in Ptolemy, this guess-work pure and simple only comes in at intervals and does not so much affect the central and, for his day, far more important tracts of the Old World, but we have yet to see how, in the mediæval period and under Arabic imagination, all geography seemed likely to become an exercise of fancy.

The chief Greek descriptions of the world, we must clearly remember, were before the mediæval workers, Christian and Moslem, from the first; these men took their choice, and the point is that they, and specially the Arabs, chose with rare exceptions the last of these, the Ptolemaic system, because it was the more ambitious, symmetrical, and pretty.

Let us trace for a moment the gradual development of this geographical mythology.

Starting with the notion of the world as a disc, or a ball, the centre of the universe, round which moved six celestial circles, of the Meridian, the Equator, the Ecliptic, the two Tropics, and the Horizon, the Arab philosophers on the side of the earth's surface worked out a doctrine of a Cupola or Summit of the world, and on the side of the heavens a pseudo-science of the Anoua or Settings of the Constellations, connected with the twelve Pillars of the Zodiac and the twenty-eight Mansions of the Moon.

With Arabic astrology we are not here concerned; it is only worth noting in this connection as the possible source of early Christian knowledge of the Southern Cross and other stars famous in the story of exploration, such as Dante shows in the first canto of his Purgatorio. But the geographical doctrines of Islam, compounded from the Hebrew Pentateuch and the theoretical parts of Ptolemy, had a more immediate and reactionary effect on knowledge. The symmetrical Greek divisions of land into seven zones or climates; and of the world's surface,[10] into three parts water and one part terra firma; the Indian fourfold arrangement of "Romeland" and the East; the similar fourfold Chinese partition of China, India, Persia, and Tartary: all these reappeared confusedly in Arabic geography. From India and the Sanscrit "Lanka," they seem to have got their first start on the myth of Odjein, Aryn, or Arim, "the World's Summit"; from Ptolemy the sacred number of 360 degrees of longitude was certainly derived, beautifully corresponding to the days of the year, and neatly divided into 180 of land or habitable earth and 180 of sea, or unharvested desert. With the seven climates they made correspond the great Empires of the world—chief among which they reckoned the Caliphate (or Bagdad), China, Rome, Turkestan, and India.

The sacred city of Odjein had been the centre of most of the earlier Oriental systems; in the Arabic form of Arim ("The Cupola of the Earth"), it became the fixed point round which circled mediæval theories of the world's shape. "Somewhere in the Indian Ocean between Comorin and Madagascar," became the compromise when the mountain could not be found off any of the known coast-lines; it was mixed up with notions of the Roc, and the Moon Mountains in Africa, of the Magnet Island and of the Eastern Kingdom made out of one vast pearl; and even in Roger Bacon it serves as an algebraic sign for a mathematical centre of the world.

The enlargement of knowledge, though forcing upon Arabic science a conviction of Ptolemy's mistake in over-extending the limits of the world known to him, only led to the invention of a scholastic distinction between the real and the traditional East and West, while the confusion was made perfect by the travestied history always so popular among Orientals. The "Gades of Alexander and Hercules," the farthest points east and west, were named after the mythical conquests of the real Iskander and the mythical hero of Greeks and Phœnicians. Arim in the middle, with the pillars of Hercules and Alexander, and the north and south poles at equal distance from it—the centre and the four corners of the world as neatly fixed as geometry could define—this was the map, first of the Arabs, and then of their Christian scholars.

To form any idea of the complete spell thus cast over thought both in Islam and Christendom, we may look at the words of European scholars of the twelfth and thirteenth centuries, living far from Islam, long after its intellectual glory had begun to decay, and at a time when Christian scholastic philosophy had reached an independent position. Gerard of Cremona and Adelard of Bath (the translator of the great Arabic geographer, Mohammed Al-Kharizmy) in the twelfth century, Roger Bacon and Albertus Magnus in the later thirteenth, are all as clear about their geographical postulates as about their theological or ethical rules. And what concerns us here is that they exactly reflect the mind of the Arabic science or pseudo-science of the time just preceding, so that their words may represent to us the state of Mohammedan thought between the eighth and twelfth centuries, between the writers at the Court of Caliph Almamoun (813–833) and Edrisi at the Court of King Roger of Sicily (1150).

(1.) Adelard, summarising Mohammed Al-Kharizmy with the results of his Paris education, tells us of the Arabic "Examination of planets and of time, starting from the centre of the world, called Arim, from which place to the four ends of the earth the distance is equal, viz., ninety degrees, answering to the fourth part of the world's circumference. It is tedious and unending to attempt to place all the countries of the world and to fix all the marks of time. So the meridian is taken as the measure of the latter and Arim of the former, and from this starting-point it is not hard to fix other countries." "Arim," he concludes, "is under the equator, at the point where there is no latitude," and he plainly implies that there were then existing among the Arabs tables calculating all the chief places of every country from the meridian of Arim.

(2.) Gerard of Cremona, who, though for some time a resident at Toledo, is essentially an Italian, tells us about the "Middle of the World," from which longitudes were calculated, "called Arim," and "said to be in India," whose longitude from west to east or from east to west is ninety degrees.

In his Theory of the Planets Gerard tells us still more wonderful things. Arim was a geographical centre known and used by Hermes Trismegistus and by Ptolemy, as well as by the great Arab geographers; Alexander of Macedon marched just as far to the east of Arim as Hercules to the west; both reached the encircling ocean, and accordingly "Arim is equidistant from both the Gades, 90 degrees; likewise from each pole, north and south, the same, 90 degrees." This all recurs in the tables of Alphonso the Wise of Castille about a.d. 1260, and two of the greatest of mediæval thinkers, Albert and Roger Bacon, reproduced the essential points of this doctrine, its false symmetry, and its balance of the true and the traditional, with variations of their own.

(3.) Albert the Great, Albertus Magnus, second only to Aquinas among the Continental Schoolmen, in his View of Astronomy, repeats Adelard upon the question of Arim, "where there is no latitude," while (4) Roger Bacon discusses not only the true and the traditional East and West, but even a twofold Arim, one "under the solstice, the other under the equinoctial zone." Arim he finds not to be in the centre of the real world, but only of the traditional. In another passage of the Opus Majus, Bacon, our first English worker in the exact sciences, allows the world-summit not to be exactly 90 degrees from the east, although so placed by mathematicians. Yet there is no contradiction, he urges, because the men of theory are "speaking of the habitable world known to them, according to the true understanding of latitude and longitude," and this "true understanding" is "not as great as has been realised in travel by Pliny and others." "The longitude of the habitable world is more than half of the whole circuit." This, reproduced in the Imago Mundi of Cardinal Peter Ailly (1410), fell into the hands of Columbus and helped to fix his doctrines of the shape of the world ("in the form of a pear") of the terrestrial paradise, and of the earth's circumference—so enormously contracted as practically to abolish the Pacific.[11]

To return to the Arabs: We have seen how they not merely followed Greek theories, which their own experience as conquerors in the Further East went to discredit, but, in the great outlines of geography, added to earlier errors, put prejudice in the place of knowledge, and handed on to Christendom a half-fanciful map of the world. It only remains for us to illustrate their leading fault, of a too vivid fancy, with a few details on minor points.

(1.) Ptolemy's "Habitable Quarter" of the world, amounting to just half the longitude of the globe, was literally accepted by the Moslem world, as it accepted the Pentateuch from the moment when it began its study of science at the Court of Almamoun (813–833). But, as the conquests of the Caliphs disclosed districts in the east far beyond Ptolemy's limits, it was necessary, in case of keeping his data for the whole, to compress the part which alone was to be found fully described in his chart: "On the west, unhappily, there were no countries newly discovered to compensate for this abridgment." By Massoudy's time—by the tenth century—fact and theory were thus hopelessly at variance.

(2.) On the shape of Africa, the mass of Arabic opinion confirmed Ptolemy, but among the more enlightened there is traceable from Massoudy's time a tendency either to react towards Strabo's partly agnostic position, or to invent some new theory rather more in harmony with the known facts. That is, either their later map-makers cut off Africa at Cape Non or Bojador and Cape Guardafui, and gave away the rest to the "Green Sea of Darkness," or, like Massoudy, they sketched a great Southern Continent, divided from Africa by a narrow channel, which connected the Western Ocean with the Sea of Habasch—of Abyssinia or India. In either case Africa was left an island.

(3.) The words "Gog and Magog" from Jeremiah, describing the nomades of Central Asia, appear in the Koran as Yadjoudj and Madjoudj. The complete story, in the tenth century and in Edrisi's day, connects them with Alexander the Great, who is also found in the Koran as Doul-Carnain, and with the Wall of China. "When the Conqueror," said the Arabs, "reached the place near where the sun rose, he was implored to build a wall to shut off the marauders of Yadjoudj and Madjoudj from the rich countries of the South." So he built a rampart of iron across the pass by which alone Touran joined Iran, and henceforth Turks and Tartars were kept outside. Till the Arabs reached the Caucasus, they generally supposed this to answer to Alexander's wall; when facts dispelled this theory, the unknown Ural or Altai Mountains served instead; finally, as the Moslems became masters of Central Asia, the Wall of China, beyond the Gobi desert, alone satisfied the conditions of shadowy but historic grandeur, beyond all practical danger of verification.

(4.) In striking contrast with the steady advance of Arabic exploration and trade in the Eastern Sea is the Moslem horror of the Western Ocean beyond Europe and Africa, the "Green Sea of Darkness" or the Atlantic. And what we have to note is that they imparted much of this paralysing cowardice to the Christian nations. Only the Northmen of Scandinavia, living a life apart, and forced to make their way over the wild North Sea, were untouched by this southern superstition, and ventured across the ocean by the Färoes, Iceland, and Greenland, to the coast of Labrador.

The doctors of the Koran indeed thought that a man mad enough to embark for the unknown, even on a coasting voyage, should be deprived of civil rights. Ibn Said goes further, and says no one has ever done this: "whirlpools always destroy any adventurer." As late as the generation immediately before Henry the Navigator, about a.d. 1390, another light of Moslem science declared the Atlantic to be "boundless, so that ships dare not venture out of sight of land, for even if the sailors knew the direction of the winds, they would not know whither those winds would carry them, and as there is no inhabited country beyond, they would run a risk of being lost in mist, fog, and vapour. The limit of the West is the Atlantic Ocean."

This was the final judgment of the Arabic race and its subject allies upon the western limits of the world, and in two ways they helped to fix this belief, derived from the timid coasting-traders of the Roman Empire on Greek and Latin Christendom. First, the Spanish Caliphate cut off all access to the Western Sea beyond the Bay of Biscay, from the eighth to the twelfth centuries. Not till the capture of Lisbon in 1147, could Christian enterprise on this side gain any basis, or starting-point. Not till the conquest of the Algarve in the extreme south-west of the peninsula, at the end of the twelfth century, was this enterprise free to develop itself. Secondly, in the darkest ages of Christian depression, the seventh, the eighth, the ninth, the tenth centuries, when only the brief age of Charlemagne offered any chance of an independent and progressive Catholic Empire in the west, the Arabs became recognised along with the Byzantines as the main successors of Greek culture. The science, the metaphysic, the abstract ideas of these centuries came into Germany, France, and Italy from Cordova and from Bagdad, as much as from Byzantium. And on questions like the South Atlantic or Indian Ocean, or the shape of Africa—where Islam had all the field to itself, and there was no positive and earlier discovery which might contradict a natural reluctance to test tradition by experiment—Christendom accepted the Arabic verdict with deference.

In the same way, on still more difficult points, such as the theory of a canal from the Caspian to the Black Sea, or from the Caspian to the Arctic circle, or from the Black Sea to the Baltic, Paris and Rome and Bologna and Oxford accepted the Arabic descriptions.

It has been necessary for us to attend to the defects of Arabic geography, in order to understand how in the long Saracen control of the world's trade routes and of geographical tradition, science and seamanship were so little advanced. Between Ptolemy and Henry of Portugal, between the second and the fifteenth centuries, the only great extension of men's knowledge of the world was: (1) in the extreme north, where the semi-Christian, semi-Pagan Vikings reached perhaps as far as the present site of New York and founded, on another side, the Mediæval Kingdom of Russia; (2) on the south-east coast of Africa, from Cape Guardafui to Madagascar, which was opened up by the trading interest of the Emosaid family (800–1300); (3) in the far east, in Central and Further Asia, by the discoveries of Marco Polo and the Friar preachers following on the tracks of the earlier Moslem travellers. The first of these was a Northern secret, soon forgotten, or an abortive development, cut short by the Tartars; the second was an Arabic secret, jealously guarded as a commercial right; the third alone added much direct new knowledge to the main part of the civilised world.

But throughout their period of commercial rule from the eighth to the twelfth centuries, the Arabs took a keen interest in land traffic, conquest, and exploration. They were of small account at sea; it took them some time to turn to their own purposes Hippalus' discovery (in the second century a.d.) of the monsoon in the Indian Ocean; but, on land, Moslem travellers and writers—generally following in the wake of their armies, but sometimes pressing on ahead of them—did not a little to enlarge the horizon of the Mohammedan world, though it was not till Marco Polo and the Franciscan missionaries of the thirteenth and fourteenth centuries, that Christian Europe shared in this gain.

As the early Caliphs conquered, they made surveys of their new dominions. Thus after Tarik and Mousa had overrun Spain, Walid at Damascus required from them an account of the land and its resources. The universal obligation of the Mecca pilgrimage compelled every Moslem to travel once in his life; and many an Arab, after the Caliphate was settled in power from the Oxus to the Pyrenees, journeyed to and fro with the joy of a master going over vast estates, shewing his dreaded turban to subjects of every nation.

This, however, was not geographical science, or even pseudo-science. Before Mohammed the Arabs had possessed some knowledge of the stars and used it for astrology; but it was at the Court of Almamoun (813–833) that their inquiring spirits first set themselves to answer the great question of geography—Where? Through the ninth and tenth centuries there arose a succession of travellers and thinkers who, with all their wild dreamings, preserved the best results of Greek maps and would have made much greater advances but for their helplessness in original work. As they could not recast Aristotle in philosophy, so they could not with all their new knowledge of the Further East recast the geography of Ptolemy and Strabo.

A few great ages, the age for instance of Almamoun in Bagdad (a.d. 830), of Mahmoud in Ghazneh (a.d. 1000), of Abderrahman III. in Cordova (a.d. 950), give us the history of Arabic geography.

Beginning in the latter years of the eighth century, Moslem science was reformed and organised, in the New Empire, by the patronage of the Caliphs of the ninth. Itineraries of victorious generals, plans and tables prepared by governors of provinces, and a freshly acquired knowledge of Greek and Indian and Persian thought, made up the subject-matter of study. The barbarism of the first believers was passing away, and Mohammed's words were recalled: "Seek knowledge, even in China." By the end of the eighth century Ptolemy's Geography and the now lost work of Marinus of Tyre had already been translated. Almamoun drew to his Court all the chief "mathematicians" or philosophers of Islam, such as Mohammed Al-Kharizmy, Alfergany, and Solyman the merchant. Further he built two observatories, one at Bagdad, one at Damascus, and procured a chart fixing the latitude and longitude of every place known to him or his savants. Al-Kharizmy interpolated the new Arabic Ptolemy with additions from the Sanscrit, and made some use of Indian trigonometry. Alfergany wrote the first Arab treatise on the Astrolabe and adopted the Greek division of the seven Climates to the new learning. Solyman, at the time of closest intercourse between China, India, and the Caliphate, travelled in every country of the Further East, sailed in the "Sea of Pitchy Darkness" on the east coast of Asia, and by his voyages became the prototype of Sinbad the Sailor.

The impulse given by Almamoun did not die with him. About 850 Alkendy made a fresh version of Ptolemy; as early as 840 the Caliph Vatek-Billah sent to explore the countries of Central Asia, and his results have been preserved by Edrisi. A few years later (c. 890) Ibn-Khordadbeh, "Son of the Magi," described the principal trade-routes, the Indian by the Red Sea from Djeddah to Scinde, the Russian by the Volga and North Caspian, the Persian by way of Balkh to China. It was by this last that some have thought the envoys of the English King Alfred went in 883, till they turned south to seek India and the Christians of San Thomé.

The early scientific movement in Islam reached its height in Albateny and Massoudy at the beginning of the tenth century. The former determined, more exactly than before, various problems of astronomical geography.[12] The latter visited every country from Further India to Spain;—even China and Madagascar seem to have been within the compass of his later travels; and his voyages in the Indian Ocean bring us to the real Sinbad Saga of the tenth century.

Sinbad, as his story appears in the Arabian Nights, has been traced to an original in the Indian tales of The Seven Sages, in the voyages of the age of Chosroes Nushirvan or of Haroun-Al-Rashid, but the tale appears to be an Arabic original, the real account, with a little more of mystery and exaggeration than usual, of the ninth-and tenth-century travellers, from Solyman to Massoudy, reproduced in form of a series of novels.[13]

With Massoudy begins also the formal discussion of geographical problems affecting Islam. Was the Caspian a land-locked sea? Did it connect with the Euxine? Did either or both of these join the Arctic Ocean? Was Africa an island? If so, was there also an unknown Southern Continent? What was the shape of South-Eastern Asia? Was Ptolemy's longitude to be wholly accepted, and if not, how was it to be bettered? By a use of Strabo and of Albateny rather than of Ptolemy, Massoudy arrived at fairly accurate and very plausible results. His chief novelties were the long river channel from the Sea of Azov to the North Sea, and the strait between South Africa and the shadowy Southern Continent. On his scheme the Indian Ocean, or Sea of Habasch, contains most of the water surface of the world, and the Sea of Aral appears for the first time in Moslem geography. Lastly his account of the Arab coasting voyages from the Persian Gulf to Socotra and Madagascar proves, implicitly, that as yet there was no use of the compass.

Massoudy cut down the girth of the world even more than Ptolemy. The latter had left an ocean to the west of Africa: the former made the Canaries or Fortunate Islands, the limit of the known Western world, abut upon India, the limit of the Eastern.

The first age of Arabic geography ends with Massoudy, its greatest name, in the middle of the tenth century. The second age is summed up in the work of the Eastern sage Albyrouny and of Edrisi, the Arabic Ptolemy (a.d. 1099–1154), who found a home at the Christian Court of Roger of Sicily. In the far East and West alike, in Spain and Morocco, in Khorassan and India, Moslem science was now driven to take refuge among strangers on the decay of the Caliphates of Bagdad and Cordova. The Ghaznevides Mahmoud and Massoud in the first half of the eleventh century, attracted to their Court not only Firdusi and Avicenna, but Albyrouny, whose "Canon" became a text-book of Mohammedan science, and who, for the range of his knowledge and the trained subtlety of his mind, stands without a rival for his time.[14] The Spanish school, as resulting directly in Edrisi, half Moslem, half Christian, like his teachers, is of still more interest. One of its first traces may be found in the Latin translation of the Arab Almanack made by Bishop Harib of Cordova in 961. It was dedicated and presented to Caliph Hakem—one of our clearest proofs of the conscious interworking of Catholic and Mahometan philosophy in the age of Pope Sylvester II. and of our own St. Dunstan. A century later, on the recapture of Toledo by Alfonso VI. (1084), an observatory was built, served by Jews and Moslems, who had been steadily producing, through the whole of the eleventh century, astronomical and geographical tables and dictionaries. A whole tribe of commentators on place-names, on the climates and constellations, and on geographical instruments was at work in this last age of the Spanish Caliphate, and their results are brought together by Abou Hamid of Granada and by Edrisi.

Born at Ceuta in 1099, this great geographer travelled through Spain, France, the Western Mediterranean, and North Africa before settling at the Norman Court of Palermo. Roger, the most civilised prince in Christendom, the final product of the great race of Robert Guiscard and William the Conqueror, valued Edrisi at his proper worth, refused to part with him, and employed men in every part of the world to collect materials for his study. Thus the Moor gained, not only for the Moslem world but for Southern Europe as well, an approximate knowledge even of Norway, Sweden, Finland, and the coasts of the White Sea. His work, dedicated to Roger and called after him, Al-Rojary, was rewarded with a peerage, and it was as a Sicilian Count that he finished his Celestial Sphere and Terrestrial Disc of silver, on which "was inscribed all the circuit of the known world and all the rivers thereof."

Each of his great Arabic predecessors, along with Eratosthenes, Ptolemy, and Strabo, was welded into his system—the result of fifteen years of abstract study, following some thirty of practical activity in travel.[15]

A special note may be made on Edrisi's account of the voyage of the Lisbon "Wanderers" ("Maghrurins") some time before 1147, the date of the final Christian capture of the Portuguese capital. For this is the earliest recorded voyage, since the rise of Islam, definitely undertaken on the Western Ocean to learn what was on it and what were its limits. The Wanderers, Edrisi tells us, were eight in number, all related to one another. They built a transport boat, took on board water and provisions for many months, and started with the first east wind. After eleven days, they reached a sea whose thick waters exhaled a fetid odour, concealed numerous reefs, and were but faintly lighted. Fearing for their lives, they changed their course, steered southwards twelve days, and so reached an island, possibly Madeira—which they called El Ghanam from the sheep found there, without shepherd or anyone to tend them. On landing, they found a spring of running water and some wild figs. They killed some sheep, but found the flesh so bitter that they could not eat it, and only took the skins. Sailing south twelve more days, they found an island with houses and cultivated fields, but as they neared it they were surrounded, made prisoners, and carried in their own boats to a city on the sea-shore, to a house where were men of tall stature and women of great beauty. Here they stayed three days, and on the fourth came a man, the King's interpreter, who spoke Arabic, and asked them who they were and what they wanted. They replied they were seeking out the wonders of the ocean and its limits. At this the King laughed heartily, and said to the interpreter: "Tell them my father once ordered some of his slaves to venture out on that sea and after sailing across the breadth of it for a month, they found themselves deprived of the light of the sun and returned without having learnt anything." Then the Wanderers were sent back to their prison till a west wind arose, when they were blindfolded and put on board a boat, and after three days reached the mainland of Africa. Here they were put ashore, with their hands tied, and so left. They were released by the Berbers, and after their reappearance in Spain, a "street at the foot of the hot bath in Lisbon," concludes Edrisi, "took the name of Street of the Wanderers."

On the other extremity of the Moslem world, on the south-east coast of Africa, there was more real progress. By Edrisi's day that important addition of Arabic travellers and merchants to the geographical knowledge of the world, by the remarkable trade-ventures of the Emosaids, had been already made.

It had taken long in the making.

THE WORLD ACCORDING TO EDRISI.

(see list of maps)

About a.d. 742, ten years after the battle of Tours, the Emosaid family, descended from Ali, cousin and son-in-law of Mahomet, tried to make Said, their clan-chieftain, Ali's great-grandson, Caliph at Damascus. The attempt was foiled, and the whole tribe fled, sailed down the Red Sea and African coast, and established themselves as traders in the Sea of India. First of all, Socotra seems to have been their mart and capital, but before the end of the tenth century they had founded merchant colonies at Melinda, Mombasa, and Mozambique, which, in their turn, led to settlements on the opposite coasts of Asia. Thus the trade of the Indian Ocean was secured for Islam, the first Moslem settlements arose in Malabar, and when the Portuguese broke into this mare clausum, in 1497–8, they found a belt of "Moorish" coast towns, from Magadoxo to Quiloa, controlling both the Indian and the inland African trades, as Ibn Batuta had found in 1330.

By Edrisi's day, moreover, the steady persistence and self-evident results of Arabic overland exploration had become recognised by a sort of "Traveller's Doctorate." It was not enough for the highest knowledge to study the Koran, and the Sunna, and the Greek philosophers at home; for a perfect education, a man must have travelled at least through the length and breadth of Islam. All the successors of Edrisi, in the twelfth and thirteenth centuries, shew this mingling of science and religion, of practical and speculative energy.

Tradition still governed Moslem thought, but there had come into being a sort of half-acknowledged appendix to tradition, made up of real observations on men and things. And in these observations, geographical interest was the main factor.

The Life of Al Heravy of Herat (1173–1215), the "Doctor Ubiquitus" of Islam in the age of the Crusades, gives us a picture of another Massoudy. The friend of the Emperor Manuel Comnenus, the "first man among Christians," Heravy seems able in his own person to break down the partition wall of religious feud by the common interest of science. In 1192 he was offered the patronage of the Crusading princes, and Richard Cœur de Lion begged for the favour of an interview, and begged in vain. Heravy, who had been on one of his exploring journeys, angrily refused to see the King whose men had broken his quiet and wasted his time. Before his death, he had run over the world (men said) from China to the Pyrenees and from Abyssinia to the Danube, "scribbling his name on every wall," and his survey of the Eastern Empire was the single matter in which Turks and "Romans" made common cause—for Greeks and Latins at Byzantium alike read Heravy, like a Christian doctor. Another example of the same catholic spirit is "Yacout the Roman,"[16] whose Dictionary, finished in the earlier half of the thirteenth century, was a summary of geographical advance since Edrisi, like the similar work of Ibn Said, of the same period.

But as a matter of fact, the balance both of knowledge and power was now shifting from Islam to Christendom. The most daring and successful travellers after the rise of the Mongols were the Venetian Marco Polo and the Friar Preachers who revived Chinese Christianity (1270–1350); Madeira and the Canaries (off Moslem Africa) were finally rediscovered not by Arabic enterprise, but by the Italian Malocello in 1270, by the English Macham in the reign of our Edward III., and by Portuguese ships under Genoese captains in 1341; in 1291 the Vivaldi ventured beyond Cape Bojador, where no Moor had ever been, except by force of storm, as in the doubtful story of Ibn Fatimah, who "first saw the White Headland," Cape Blanco, between Cape Bojador and Cape Verde.

In the fourteenth century the map of Edrisi was superseded by the new Italian plans and coast-charts, or Portolani. As the Moslem world fell into political disorder, its science declined. "Judicial astrology" seemed gaining a stronger and stronger hold over Islam, and the irruption of the Turks gradually resulted in the ruin of all the higher Moslem culture. Superstition and barbarism shared the honour and the spoils of this victory.

But two great names close the five hundred years of Arab learning.

1. Ibn Batuta (c. 1330), who made himself as much at home in China as in his native Morocco, is the last of Mohammedan travellers of real importance. Though we have only abridgments of his work left to us, Colonel Yule is well within his rights in his deliberate judgment, "that it must rank at least as one of the four chief guide books of the Middle Ages," along with the Book of Ser Marco Polo and the journals of the two Friar-travellers, Friar Odoric and Friar William de Rubruquis.

2. With Abulfeda the Eastern school of Moslem geography comes to an end, as the Western does with Ibn Batuta. In the early years of the fourteenth century he rewrote the "story and description of the Land of Islam," with a completeness quite encyclopædic. But his work has all the failings of a compilation, however careful, in that, or any, age. It is based upon information, not upon inspection; it is in no sense original. As it began in imitation, so it ended. If it rejects Ptolemy, it is only to follow Strabo or someone else; on all the mathematical and astronomical data its doctrine is according to the Alexandrians of twelve hundred years before, and this last précis of the science of a great race and a great religion can only be understood in the light of its model—in Greek geography.