History of the Intellectual Development of Europe, Volume II (of 2). Draper John William

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СКАЧАТЬ their acquirements being a passport to them wherever they went, and a sufficient introduction to any of the African or Asiatic courts. They were thus continually brought in contact with men of affairs, soldiers of fortune, statesmen, and became imbued with much of their practical spirit; and hence the singularly romantic character which the biographies of many of these men display, wonderful turns of prosperity, violent deaths. The scope of their literary labours offers a subject well worthy of meditation; it contrasts with the contemporary ignorance of Europe. Some wrote on chronology; some on numismatics; some, now that military eloquence had become objectless, wrote on pulpit oratory; some on agriculture and its allied branches, as the art of irrigation. Not one of the purely mathematical, or mixed, or practical sciences was omitted. Their continued inclination to the study of medicine. Out of a list too long for detailed quotation, I may recall a few names. Assamh, who wrote on topography and statistics, a brave soldier, who was killed in the invasion of France, A.D. 720; Avicenna, the great physician and philosopher, who died A.D. 1037; Averroes, of Cordova, the chief commentator on Aristotle, A.D. 1198. It was his intention to unite the doctrines of Aristotle with those of the Koran. To him is imputed the discovery of spots upon the sun. The leading idea of his philosophy was the numerical unity of the souls of mankind, though parted among millions of living individuals. He died at Morocco. Abu Othman wrote on zoology; Alberuni, on gems – he had travelled to India to procure information; Rhazes, Al Abbas, and Al Beithar, on botany – the latter had been in all parts of the world for the purpose of obtaining specimens. Ebn Zoar, better known as Avenzoar, may be looked upon as the authority in Moorish pharmacy. Pharmacopœias were published by the schools, improvements on the old ones of the Nestorians: to them may be traced the introduction of many Arabic words, such as syrup, julep, elixir, still used among apothecaries. Relics of the Arab vocabulary. A competent scholar might furnish not only an interesting, but valuable book, founded on the remaining relics of the Arab vocabulary; for, in whatever direction we may look, we meet, in the various pursuits of peace and war, of letters and of science, Saracenic vestiges. Our dictionaries tell us that such is the origin of admiral, alchemy, alcohol, algebra, chemise, cotton, and hundreds of other words. The Saracens commenced the application of chemistry, both to the theory and practice of medicine, in the explanation of the functions of the human body and in the cure of its diseases. Their medicine and surgery. Nor was their surgery behind their medicine. Albucasis, of Cordova, shrinks not from the performance of the most formidable operations in his own and in the obstetrical art; the actual cautery and the knife are used without hesitation. He has left us ample descriptions of the surgical instruments then employed; and from him we learn that, in operations on females in which considerations of delicacy intervened, the services of properly instructed women were secured. How different was all this from the state of things in Europe; the Christian peasant, fever-stricken or overtaken by accident, hied to the nearest saint-shrine and expected a miracle; the Spanish Moor relied on the prescription or lancet of his physician, or the bandage and knife of his surgeon.

      Liberality of the Asiatic khalifs. In mathematics the Arabians acknowledged their indebtedness to two sources, Greek and Indian, but they greatly improved upon both. The Asiatic khalifs had made exertions to procure translations of Euclid, Apollonius, Archimedes, and other Greek geometers. Almaimon, in a letter to the Emperor Theophilus, expressed his desire to visit Constantinople if his public duties would have permitted. He requests of him to allow Leo the mathematician to come to Bagdad to impart to him a portion of his learning, pledging his word that he would restore him quickly and safely again. "Do not," says the high-minded khalif, "let diversity of religion or of country cause you to refuse my request. Do what friendship would concede to a friend. In return, I offer you a hundred weight of gold, a perpetual alliance and peace." True to the instincts of his race and the traditions of his city, the Byzantine sourly and insolently refused the request, saying that "the learning which had illustrated the Roman name should never be imparted to a barbarian."

       Their great improvements in arithmetic. From the Hindus the Arabs learned arithmetic, especially that valuable invention termed by us the Arabic numerals, but honourably ascribed by them to its proper source, under the designation of "Indian numerals." They also entitled their treatises on the subject "Systems of Indian Arithmetic." This admirable notation by nine digits and cipher occasioned a complete revolution in arithmetical computations. As in the case of so many other things, the Arab impress is upon it; our word cipher, and its derivatives, ciphering, etc., recall the Arabic word tsaphara or ciphra, the name for the 0, and meaning that which is blank or void. Mohammed Ben Musa, said to be the earliest of the Saracen authors on algebra, and who made the great improvement of substituting sines for chords in trigonometry, wrote also on this Indian system. He lived at the end of the ninth century; before the end of the tenth it was in common use among the African and Spanish mathematicians. Ebn Junis, A.D. 1008, used it in his astronomical works. From Spain it passed into Italy, its singular advantage in commercial computation causing it to be eagerly adopted in the great trading cities. We still use the word algorithm in reference to calculations. The study of algebra was intently cultivated among the Arabs, who gave it the name it bears. Ben Musa, just referred to, was the inventor of the common method of solving quadratic equations. Their astronomical discoveries. In the application of mathematics to astronomy and physics they had been long distinguished. Almaimon had determined with considerable accuracy the obliquity of the ecliptic. His result, with those of some other Saracen astronomers, is as follows:

      Almaimon had also ascertained the size of the earth from the measurement of a degree on the shore of the Red Sea – an operation implying true ideas of its form, and in singular contrast with the doctrine of Constantinople and Rome. While the latter was asserting, in all its absurdity, the flatness of the earth, the Spanish Moors were teaching geography in their common schools from globes. In Africa, there was still preserved, with almost religious reverence, in the library at Cairo, one of brass, reputed to have belonged to the great astronomer Ptolemy. Al Idrisi made one of silver for Roger II., of Sicily; and Gerbert used one which he had brought from Cordova in the school he established at Rheims. It cost a struggle of several centuries, illustrated by some martyrdoms, before the dictum of Lactantius and Augustine could be overthrown. Among problems of interest that were solved may be mentioned the determination of the length of the year by Albategnius and Thebit Ben Corrah; and increased accuracy was given to the correction of astronomical observations by Alhazen's great discovery of atmospheric refraction. Among the astronomers, some composed tables; some wrote on the measure of time; some on the improvement of clocks, for which purpose they were the first to apply the pendulum; some on instruments, as the astrolabe. The introduction of astronomy into Christian Europe has been attributed to the translation of the works of Mohammed Fargani. In Europe, also, the Arabs were the first to build observatories; the Giralda, or tower of Seville, was erected under the superintendence of Geber, the mathematician, A.D. 1196, for that purpose. Its fate was not a little characteristic. After the expulsion of the Moors it was turned into a belfry, the Spaniards not knowing what else to do with it.

      Europe tries to hide its obligations to them. I have to deplore the systematic manner in which the literature of Europe has contrived to put out of sight our scientific obligations to the Mohammedans. Surely they cannot be much longer hidden. Injustice founded on religious rancour and national conceit cannot be perpetuated for ever. What should the modern astronomer say when, remembering the contemporary barbarism of Europe, he finds the Arab Abul Hassan speaking of tubes, to the extremities of which ocular and object diopters, perhaps sights, were attached, as used at Meragha? what when he reads of the attempts of Abderrahman Sufi at improving the photometry of the stars? Are the astronomical tables of Ebn Junis (A.D. 1008), called the Hakemite tables, or the Ilkanic tables of Nasser Eddin Tasi, constructed at the great observatory just mentioned, Meragha, near Tauris, A.D. 1259, or the measurement of time by pendulum oscillations, and the methods of correcting astronomical tables by systematic observations – are such things worthless indications of the mental state? The Arab has left his intellectual impress on Europe, as, before long, Christendom will have to confess; he has indelibly written it on the heavens, as any one may see who reads the names of the stars on a common celestial globe.

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