For example, Almansor, who reigned as Caliph from A. D. 753 to 775, established the University of Bagdad, and endowed it with two hundred thousand pieces of gold, and an annual revenue of fifteen thousand dinars, equal in commercial value to one hundred and twenty thousand dollars of our money. He invited thither learned men from every land, irrespective of their religious opinions. By these men were founded celebrated schools of mathematics, astronomy, chemistry, medicine, law and languages.
His grand-son, Haroun-al-Raschid, ordered in A. D. 786, that a public school should be attached to every mosque in his dominions. This was more than seven hundred years before the establishment of the famous parish schools of Scotland.
The Caliph-al-Mamun, in A. D. 813, founded the great medical college of Cairo, which required students to pass a rigid examination before receiving authority to enter on the practice of their profession. At this college we have the first account of dissecting human bodies for the purpose of ascertaining the nature and locality of diseases, and the first circulating library for students. These books were bound according to the modern form, which then began to be used among the Saracens in place of the ancient form of the scroll.
By the means just mentioned, the ancient sciences were greatly extended and new ones introduced. To the Saracens we are indebted for our present system of arithmetical notation. If, for example, we wish to multiply 1882 by 125 and then attempt it by the ancient method MDCCCLXXXII., multiplied by CXXV., we shall soon perceive the vast superiority of the Arabic system over that formerly in use. No wonder, then that under the ancient system those who were engaged in solving difficult mathematical problems were frequently styled "sweating calculators."
In this case as in many others the Arab has left his impress on this science. For instance, our word cipher, and kindred words, such as decipher, ciphering, etc., are derived from the word tsaphara, or ciphra, the name for the 0 in the Arabic language.
In experimental sciences, they originated chemistry and discovered the nature and properties of sulphuric acid, nitric acid, alcohol and many other chemical agents. From their schools of medicine may be traced such words as julep, syrup, elixir, alchemy, etc. To them we are indebted for algebra, or universal arithmetic, and in astronomy they made such advances that many constellations and stars of the first magnitude still retain the Arabic names.
In geography, the Saracens made important discoveries. Hitherto mankind had been taught that the earth was a vast plain, surmounted by an immense vault commonly called the sky. They were the first to prove that the earth is a vast globe, or ball; and in order to determine its size, they first ascertained on the level shore of the Red sea the exact position of the North Star. Then traveling directly north until it had attained another degree of elevation, they measured the distance between these points, and multiplying the result by three hundred and sixty (the number of degrees in a circle), they found the earth to be nearly twenty-five thousand miles in circumference. So accurate were their observations and measurements that the best calculators of recent times differ from them less than one-third of a mile.
Five hundred years later the Roman pontiffs were excommunicating and torturing those who taught the rotundity of the earth. While Catholic monks were teaching, in all its absurdity, the flatness of the earth, and how it rested on a vast rock, and that rock on another and so on all the way down to the bottom(?), the Saracens were teaching geography from globes in their common schools. It cost a long struggle through several centuries, "with spiritual wickedness in high places," before the truth finally triumphed.
European historians have generally given great credit to Pope Gregory for the invention and adoption of the Gregorian calendar and a more accurate method of measuring the exact length of the civil year. Yet, Gregory only adopted what had been discovered and taught by Thebit-Ben-Corrah, the Saracen astronomer, more than five hundred years before, and what Gregory himself had learned in youth while attending a Saracen university.
The mariner's compass was well known to the Arabs, who probably brought it from China and introduced it to the nations of Europe. From this we may correctly infer that they were a maritime people. In fact, long before the time of Mahomet, Arabian merchants were acquainted with the Indies, and even China and the eastern coast of Africa as far south as Madagascar.