To the Moslems we owe the adaptation of the magnetic needle to the purposes of navigation, an invention long erroneously attributed to the sailors of Amalfi. Its peculiar properties, familiar for ages to the Chinese, were probably communicated by them to the Arabs. Originally inserted in a cork and permitted to float on the surface of water, the Moors were the first to mount it on a pivot, thereby vastly increasing its utility and accuracy. They were evidently acquainted with it before the twelfth century, as Arab writers of that epoch allude without comment to the compass as an instrument perfectly familiar to the seamen of the Mediterranean. To the Mussulman the magnet possessed a threefold significance and value. It guided his vessel across the trackless waters independently of the appearance of the stars. It indicated unerringly the course of the caravan in the Desert, constantly menaced by the perils of thirst and of the simoom. And it enabled the pious worshipper, however distant from the Mosque of Mecca, to ascertain in an instant the point to which he should direct his face during the hours of prayer.
The laborious and exhaustive investigations of Reinand, Favé, Le Bon, and Viardot have demonstrated beyond dispute that the Arabs were the inventors of gunpowder and artillery. While it was admitted that these destructive agents were introduced into Europe by the Moors of Spain, their discovery was long universally ascribed to the Chinese. As a matter of fact, they were first made use of in Syria and Egypt, probably as early as the beginning of the thirteenth century. The primitive lombards of the Sultan of Egypt, which cast great balls of stone, terrified the army of St. Louis in 1249. Artillery was employed by the Moors, besieged in Niebla by Alfonso X., in 1257. According to Ibn-Khaldun, it was used by Abu-Yusuf, Emir of Morocco, at the siege of Sidjilmesa, in 1273. Ibn-al-Khatib says that cannon were made in Granada before 1300, and mentions Ibn-al-Hadj as famous for his skill in their manufacture. After that time they are frequently mentioned by the Spanish historians of the Reconquest. Their first appearance in the wars of France was in 1338. The Earls of Salisbury and Derby, who served in the army of Alfonso XI., before Algeziras, in 1342, carried the knowledge of the invention to England four years before the battle of Crecy, an epoch which marks its general adoption in Europe. Considering the immense military superiority which we should naturally attribute to a people exclusively acquainted with the formula for the manufacture of gunpowder and experienced in its application to fire-arms, it is remarkable that this enormous power was not more profitably utilized by the Spanish Arabs, who possessed it a century before the portentous secret became known to the nations of Christendom.
Among the Moslems, the operations of war were rarely carried on according to a definite plan. Military service was not merely a matter of patriotism or loyalty, it was a religious duty imposed by his faith upon every Mussulman, and from which only the infirm and the aged were exempt. As of old in the Desert, each clan marched under its hereditary commander. In important campaigns the army was marshalled in five grand divisions, symbolical of the five cardinal precepts of Islam, an arrangement by which the valor of the warrior was strengthened by the stimulus of fanatical zeal. The Koran was always in sight, either borne like a standard on the point of a lance or held in the hand of the general, as he directed the manœuvres of the field. There was no regular attempt at organization. The troops depended largely on the enemy for subsistence. The cavalry were generally clad in mail; the infantry were, as a rule, little better than a half-armed rabble. If repulsed at the first onset, it was almost impossible to rally a Moslem army.
Among the most remarkable institutions of the Arabs of Spain was the Ribat, or station on the frontier of the enemy, which formed the model of the orders of military monks of the Middle Ages. These establishments were strongly fortified castles, garrisoned by devout soldiers, who expected the recompense promised by the Koran for constant service against the infidel. The leisure time of their occupants was spent in religious exercises. Many pious volunteers sought glory and holiness in the dangerous life which the exposed position of these outposts afforded. The latter guarded the passes of every hostile country; they were found on the borders of Italy, Languedoc, Castile, Aragon, Portugal. Their rules of discipline, their vows, and their penances presented a striking analogy to those of the orders of Santiago, Alcantara, and Calatrava, whose organization they evidently suggested. Their foundation preceded those of the Hospital and the Temple by more than two hundred and fifty years.
The coinage of the Ommeyades of Spain was the purest, the most artistic in design, the most elegant in execution, which had to that time been known in Europe. It was composed of the dinar, of gold, equal to two dollars; the dirhem, of silver, equal to twelve cents; and various small pieces of copper of fluctuating value.
The balance, whose value to the merchant would not be fully apparent unless he were deprived of it, is also an invention of the Arabs. The Moorish unit of linear measure was represented by a horsehair. Six of these placed together were equal to a grain of barley; six grains of barley made a finger-breadth; four fingers a palm; six palms a cubit. Of modern weights in ordinary use, the grain, represented by a barley-corn, and the carat, adapted from the seed of the pea, have descended without alteration from the Arabs to our goldsmiths and jewellers.
The political, religious, and domestic institutions of the Arabs, which account in a measure for the amazing rapidity of their progress in Europe as elsewhere, were also largely responsible for the downfall of their power. Their government, derived from the patriarchal organization of the Desert and confirmed by the revered precepts of Islam, placed absolutely unlimited authority in the hands of the sovereign. The khalif, as the word implies, was the Successor of the Prophet. Fortune was long eminently propitious to the Ommeyade dynasty in providing it with a line of kings even more distinguished in the arts of peace than in the arduous and uncertain achievements of conquest. But these talents for administration and war, it is obvious, could not be indefinitely transmitted. With the first appearance of royal incapacity, the sceptre passed into the hands of ambitious statesmen, ready to sacrifice the claims of religion and hereditary descent to considerations of private emolument and distinction. The epoch included in the reign of Hischem II. is the most glorious in Moslem annals. But that renown was achieved not by the Khalif in person, nor even under his direction, but by Al-Mansur, his Prime Minister, who, although of obscure birth, guided, as did the Frankish Mayors of the Palace, by his transcendent and unaided genius the destinies of the empire. The example of his success and the attempt to bequeath to his son the power which he alone was able to wield were fatal to the Moslem domination, and contributed with other causes of equal gravity to its ultimate overthrow.
In the civil and military organization of the government the patriarchal traditions of the Bedouin were preserved, under circumstances little suggestive of his origin and highly incongruous and inexpedient, amidst the results of an advanced civilization. The authority and office of the sheik were reproduced under other names, which, even to the ignorant foreigner, did not serve to disguise their identity. Founded equally upon the legislation of the Koran, the administrations of the Sultans of Bagdad and the Khalifs of Cordova differed only in the most trifling details. Under both, the prince was daily accessible to the complaints, and redressed in person the grievances of his subjects. Under both, the kadi, whose office was invested with a certain degree of sanctity as well as of secular power, dispensed justice at the portals of the mosque. His position was rather sacerdotal than judicial. He was one of the interpreters of the Koran, the original source of all Moslem jurisprudence. In his appointment the greatest care was exercised. Only individuals conspicuous for learning, experience, and integrity were considered eligible to such a responsible employment. Even the Khalif obeyed his summons. The Chief Kadi, who had supervision over all the others, was the most powerful dignitary of the empire.
The Arabs left no extensive code of laws like that of the Visigoths, wherein the rights of persons and the penalties of crimes are systematically enumerated and defined. As their government was presumed to be theocratic, its principles were necessarily unalterable. Of legislation, in the modern understanding of the term, they knew nothing. The decrees of the khalifs, based upon the construction of the Koran and the traditionary opinions of the Prophet embodied in the Sunnah, formed the entire body of legal principles and precedents available for the instruction and guidance of magistrates.
Among the other officials of the administration were the Hajib, or Prime Minister; the Viziers, who composed the Divan or Council; and the Katibs, or Secretaries. All of them were mere advisers of the sovereign, and their authority was, except under extraordinary circumstances, only nominal.