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46 [74] CALLINICUS BEDE
earth, which a few Hindu astronomers supported. The most notable feature of the book is the application of algebraic methods to astronomical problems. Hindu mathe maticians were indeed of prime service to the world, for sometime within the next two centuries some nameless mathe matician devised the notion of a symbol for “zero.” This made positional notation practical, and a number system based on such notation was adopted. It spread to Arabs such as al-Khwarizmi [79] and from them was introduced (as the “Ara bic numerals” we use today) to Europe by men such as Fibonacci [95]. [74] CALLINICUS (kal-ih-nyTcus) Born: Heliopolis, Egypt (?), about 620 Died: date unknown Actually, nothing at all is known about the personal life of Callinicus. The birth date given above is not more than an educated guess, and some think he was bom in Syria rather than in Egypt or that he was Jewish rather than Chris tian. Whether Syrian or Egyptian, Jewish or Christian, he fled to Constantinople ahead of the conquering Arabian armies and in Constantinople invented Greek fire. This was a mixture containing an inflammable petroleum fraction, plus potassium nitrate to supply oxygen, plus quicklime perhaps to supply further heat through reaction with water. The exact secret of the composition is lost, but be cause of the nature of modern war weapons, Greek fire is not important to rediscover, except out of historical curi osity. It burned on water and therefore could be used to destroy a wooden fleet. The Greeks of the Byzantine Empire used Greek fire in 670 to repel the ships of an Arabic naval onslaught on Con stantinople and in this way, this one in vention, an authentic “secret war weapon,” may well have radically changed the course of history. It may be that Constantinople would have fallen without the use of Greek fire. If so, it is possible that the Muhammadan faith would have swept Europe. [75] BEDE (beed) English scholar
When the Germanic invaders had sub merged Roman civilization in the West, those scraps of ancient learning re mained that were preserved by the monk ish copyists and summarizes. One of the most notable of these was Bede. He received an ecclesiastical training from childhood, having entered the mon astery at Jarrow, where he was to spend his life, at the age of seven. He was finally ordained priest at thirty and might eventually have become an abbot, but he refused higher office in order to write. This he did, spending a quiet and idyllic life immersed in his writing and his religious duties, never traveling more than fifty miles from home. He is commonly called the Venerable Bede, this being an old-fashioned ecclesi astical title. Some, taking the word in its later meaning, have thought it referred to extreme age and put forth the notion that he lived a hundred years or more. This is not so. In his writings Bede gives an account of the history of the early centuries of Anglo-Saxon England, and also all the knowledge he has managed to accumu late. This consisted largely of bits of Pliny [61]. He also deals with such as tronomy as was necessary for the proper dating of Easter, concerning which there was much controversy in his time. He noted that the vernal equinox had slipped to a point three days earlier than the traditional March 21. This imper fection of Sosigenes’ [54] Julian calendar was to lead to a reform and a slight ad justment of the number of leap years per millennium. The reform did not come in a hurry, though; it came nine centuries after Bede’s observation. He maintained that the earth was a sphere, and even this much was valuable at a time when scholarship in western Europe was close to bottom. Nor was it only the most primitive bits of knowl edge he preserved. He revived the sug gestion of Pytheas [39] that the tides were governed by the phases of the
[76] GEBER
GEBER [76] moon, an effect that was to escape the great Galileo [166] nine centuries later. He also realized, like Seleucus [51], eight centuries before, that high tide did not occur everywhere at once and that tide tables had to be prepared separately for each port. This is considered the only original scientific contribution in western Europe, during some eight centuries after the end of Greek learning. A more trivial point, but one that affects us all very intimately, is that in his historical works he dated events from the birth of Jesus rather than from the creation of the world. In this respect, we have all come to follow him. Bede worked to the last, completing his translation of St. John on his death bed. He was canonized in 1899 by Pope Leo XIII and is a Doctor of the Church. [76] GEBER (jee'ber); Arabic name, ABU MUSA JABIR IBN HAY- YAN
Arabian alchemist Born: possibly in Al-Kufah (in what is now Iraq), about 721 Died: possibly in Al-Kufah, about 815
After the coming of the prophet Mu hammad, the Arabian tribes, in a great burst of expansionist energy, swept over western Asia and northern Africa. They disrupted, but did not destroy, the East ern Roman Empire, which had survived the barbarian onslaughts that had wiped out the empire in the West. The Eastern Empire, particularly after the Arabian conquests, came to be known as the Byzantine Empire after its capital, By zantium.
The Arabs occupied Syria in the 630s and Egypt in the 640s. In so doing, they fell heir to much of Greek science, and this proved of importance and even benefit to the history of science. The ad vance of science in what remained of Roman dominions came to a complete halt. For a thousand years of Byzantine history the only name worth mentioning is Callinicus [74]. Western Europe was in darkness. It was the Arabs alone who were in a position to preserve and trans mit the accumulated knowledge of the ancients. They not only preserved but also, in some cases, made advances, notably in alchemy. The first of the important Ara bian alchemists was Geber (as he was known to Europeans after his works were translated into Latin) and he was also the best. He carried the science far beyond the point it had reached in the time of Zosimus [67]. Geber’s lifetime corresponded with the very height of Arabic power, falling as it did at the time of the reign of the cele brated Harun al-Rashid, the famous Caliph of the Thousand and One Nights. Geber, the son of a druggist, was a personal friend of Harun’s vizier Ja’far al-Sadiq, and was also an adherent, it would seem, of the sect of the Sufis, which gave rise to the notorious Assas sins (who fed on hashish—hence their name—and performed political assassi nations on command). The sect was never popular with outsiders, and small wonder. Then, to make matters worse, Ja’far fell from power and was executed. On both scores, Geber felt his life inse cure. He went into retirement in his na tive village and there died in peace. Meanwhile, though, he had written nu merous works on alchemy. It is doubtful that all the books attributed to him are really his, for later alchemists often at tempted to gain greater respect for then- work by attributing them to an earlier man of renown. This remained true as long as the publication of books was a matter of arduous hand labor so that only comparatively few could appear in any numbers at all. It was only after the invention of printing, when almost any one could see his book appear in large editions, that the habit of surrendering credit died out. The older habit seems saddest when a great man of science retreats into un deserved anonymity by his own choice. Thus, a much later alchemist wrote under Geber’s name and is now known only as the “false Geber” [107]. Geber’s most influential contribution to alchemy was his modification of the
[77] ALCUIN
CHARLEMAGNE [78] Greek doctrine of the four elements. Geber felt that these combined to form two different kinds of solid substances— sulfur and mercury. The former was the idealized principle of combustibility, the latter that of metallic properties. By the appropriate combination of the two any metal could be formed. Therefore, lead could be separated into sulfur and mer cury, which could then be recombined in new proportions to form gold. This transmutation could be brought about through a mysterious substance that he, or later Arabs, called al-iksir from a Greek word for a dry, medicinal powder. This came down in Latin as “elixir.” Following Geber’s initial impulse, al chemists for a thousand years sought this “philosopher’s stone,” as the dry material was popularly termed. Since any sub stance capable of forming gold must also have other miraculous properties, alche mists surmised it could cure all disease, restore youth, confer immortality. It was therefore also named the “elixir of life.” Among these mistaken theories, how ever, Geber published accurate descrip tions of valuable chemical experiments. He described ammonium chloride and showed how to prepare white lead. He prepared weak nitric acid and he also distilled vinegar to obtain strong acetic acid. He worked with dyes and varnishes and dealt with methods for refining metals. Most important, he described various chemical operations with great care.
Unfortunately, later alchemists fol lowed Geber’s mistaken theories into wilder and deeper morasses. For the most part they abandoned Geber’s sys tem of practical, straightforward descrip tions of worthwhile experiments. [77] ALCUIN (al'kwin) English scholar Born: York, about 732 Died: Tours, France, May 19, 804 Alcuin’s teacher had been a pupil of Bede [75] and Alcuin carried on the earlier scholar’s tradition. The school at York, where he studied, was the most re nowned in its time, in western Europe, and in 778, Alcuin became its head. However, he never rose beyond the sta tus of deacon. Alcuin visited Rome in 781 and there he met Charlemagne [78], The latter, having established a strong rule over most of western Europe, aspired to cul ture. He therefore invited Alcuin to serve as head of an educational system for his empire. Alcuin accepted and brought English learning (little enough, but better, at the moment, than anything available in Charlemagne’s dominions) to the continent. Charlemagne himself learned to read under Alcuin’s tutelage, though writing remained beyond his powers. Alcuin was installed at Tours as abbot and there es tablished a school where scribes were trained for the careful copying of manu scripts. In order to crowd as much writ ing as possible onto a piece of parch ment, yet leave it legible, Alcuin de signed a way of writing in condensed fashion (“Carolingian minuscule” from Carolus [Magnus], the Latin name of Charlemagne) which is the ancestor of our “small letters.” Under Alcuin’s influence, there was a brief graying (the Carolingian Renais sance) of the darkness, which, however, soon returned. The first slow glimmers of the actual dawn were still more than two centuries in the future. [78] CHARLEMAGNE (shahr-luh- main')
Frankish emperor Born: Aachen, Germany, about 742
Died: Aachen, January 28, 814 Charlemagne is one of the great mon- archs of Western tradition and one about whom myths have clustered with almost the same fantastic concentration that they cling to the legendary Arthur of Britain. For our purposes, however, his impor tance lay in his realization that his realm lay under a barbarous blanket of igno rance that was both disgraceful and dan gerous to any state aspiring to prosperity 49 [79] AL-KHWARIZMI THABIT IBN QURRA
and greatness. In 789 he began to estab lish schools in which the elements of mathematics, grammar, and ecclesiastical subjects could be taught, and Alcuin [77] was made the educational coordinator of the empire. Charlemagne himself undertook to learn to read and write, and managed the former. There are touching tales of his unsuccessful efforts to force his fingers, in mature life, to shape the tiny letters properly and his failure to do so. The Carolingian Renaissance did not outlast the great Charles, but no spark of light truly dies, perhaps, and his work left dim traditions that were to be car ried onward a few centuries later. [79] AL-KHWARIZMI, Muhammad ibn Musa (al-khwah'riz-mee) Arabian mathematician
in the Uzbek SSR of the Soviet Union), about 780
Al-Khwarizmi’s best claim to immor tality lies in a word in the title of a work in which he preserved and extended the mathematics of Diophantus [66], The title of his book was ilm al-jabr wa’l muqabalah, which means “the science of transposition and cancellation.” The Ara bic word al-jabr (“transposition”) be came “algebra” in the Latin translitera tions of the title and that in turn became the name of the entire branch of mathe matics that Diophantus had founded. It is the branch that involves the solution of equations by such devices as transpo sitions and cancellations. Al-Khwarizmi’s own name was dis torted into “algorism,” which came to mean “the art of calculating,” something we now call “arithmetic.” (“Arithmetic” when used in ancient times is what we now call “theory of numbers.”) A more important contribution at tributed to al-Khwarizmi rests on the fact that he drew on Hindu sources as well as Greek, for he picked up the Hindu numerals, including the zero. When his work was translated into Latin, those numerals (miscalled “Arabic nu merals”) were transmitted to Europe via the work of Fibonacci [95], Their slow adoption revolutionized mathematical manipulations, making long division, for instance, a technique for children, rather than for experts only. While an improved symbolism does not directly advance science it does free men from undue preoccupation with mere techniques and makes possible fur ther advances in theory by simply giving them more time to think. Al-Khwarizmi was supported by the Caliph Mamun, under whom the power of Baghdad reached its height. (Mamun ruled from 813 to 833.) With that sup port, al-Khwarizmi prepared a world ge ography based largely on Ptolemy [64], In contrast to Ptolemy, al-Khwarizmi overestimated the size of the earth, giv ing it a circumference of forty thousand miles. [80] THABIT IBN QURRA Arabian mathematician Born: Harran, in what is now southeastern Turkey, 836 Died: Baghdad, February 18, 901 Although Thabit lived in a Muslim so ciety, he was not a Muslim but was a member of a Sabian sect that traced back to the pre-Muslim Babylonian soci ety. He was to the Muslims what the Neo-Platonists were to the Christians. He came of wealthy parents; he was himself a money changer; and he was apparently an accomplished linguist, being fluent in both Greek and Arabic, in addition to his native Syriac. An Ara bic mathematician, encountering him and admiring his knowledge and obvious intelligence, invited him to come to Baghdad where he would have the chance to obtain a thorough education. This he did and to such good effect that he became a great scholar; this meant that when he returned home, he was greeted with the utmost hostility by his own sect, which accused him as hav ing left the fold. He was condemned by their religious court and it seemed only prudent to him to return to Baghdad, where he remained the rest of his life. 5 0
[81] ALFRED THE GREAT ALBATEGNIUS
There he advanced rapidly and was in the retinue of the Caliph al-Mutadid. He translated many of the works of the Greek scientists; and wrote commen taries on them as well, thereby becoming a powerful factor in making Greek sci ence available to the Muslim world. He himself also did work of his own, particularly in mathematics and, for in stance, considered the matter of Euclid’s parallel postulate, something that nearly a thousand years later, at the hands of Bolyai [530] and Lobachevski [484] would lead to non-Euclidean geometry.
English monarch Born: Wantage, Berkshire, 849 Died: Winchester, Hampshire, October 28, 900 In the deepest Dark Ages, Alfred the Great, like Charlemagne [78], offered a spark of light, an earnest of things to come in the slowly developing west Eu ropean civilization that was arising out of the ruins of the classical world. Alfred is best known for his indomi table battles against the Danish invaders, battles through which his persistence, bravery, and skill finally saved half the island and kept it firmly in Saxon hands. Both for his accomplishments and his character, Alfred was clearly the best of the Anglo-Saxon rulers of England. Alfred was not merely interested in learning for himself but felt a deep con cern that his subjects have learning avail able to them. For that reason he made every effort to have worthwhile Latin books translated into Anglo-Saxon. He did much of the work himself, translat ing the works of Boethius [71] and Bede [75]. [82] RHAZES (ray'zeez); Arabic name, ABU-BAKR MUHAMMAD IBN ZAKARIYYA AR-RAZI Persian physician and alchemist
heran, in what is now Iran), about 845
Rhazes (the Latinized version of his name) had no such close connection with the caliph’s court as Geber [76], but he at least had the distinction of being born in Harun al-Rashid’s hometown. In 880 or thereabouts Rhazes visited Baghdad and there, so we are told, came across an old apothecary who fascinated him with stories of medicine and disease. Rhazes decided to study medicine and ended as chief physician of Baghdad’s largest hospital. He is supposed to have been the first to differentiate clearly be tween smallpox and measles. Rhazes, like Geber, described his ex periments so carefully that modern chemists can repeat them and check on his work. He prepared what we now call plaster of Paris, for instance, and de scribed the manner in which it could be used to form casts holding broken bones in place. He also studied and described metallic antimony. He shared with Aristotle [29] a delight in classifying and was the first, so far as is known, to divide all substances into the grand classification of animal, vege table, and mineral. He also subclassified minerals into metals, volatile liquids (spirits), stones, salts, and so on; a divi sion that was much the most useful up to his time. He went along with Geber’s notions concerning mercury and sulfur as the basic ingredients of solid substances and added to it salt as a third. He was a thoroughgoing rationalist, by the way, who dismissed miracles and mysticism. He thought religion harmful as the cause of hatred and wars. He ac cepted a materialist atomism as his view of the universe. Naturally, he was greatly vilified for these views. [83] ALBATEGNIUS (al-buh-teg'nee- us); Arabic name, ABU-’AB DULLAH MUHAMMAD IBN JABIR AL-BATTANI Arabian astronomer
southeastern Turkey), about 858 Died: near Samarra, Iraq, 929 Greek astronomy as finally refined by Ptolemy [64] was preserved by the
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