The skill of Oriental peoples as mechanics and engineers is proved by their success as builders. The great pyramids exactly face the points of the compass. The principle of the round arch was known in Babylonia at a remote period The transportation of colossal stone monuments exhibits a knowledge of the lever, pulley, and inclined plane. [22] Babylonian inventions were the sundial and the water clock, the one to register the passage of the hours by day, the other by night. The Egyptians and Babylonians also made some progress in the practice of medicine. [Illustration: A BABYLONIAN MAP OF THE WORLD A tablet of dark brown clay, much injured, dating from the 8th or 7th century B.C. The two large concentric circles indicate the ocean or, as it is called in the cuneiform writing between the circles, the 'Briny Flood.' Beyond the ocean are seven successive projections of land, represented by triangles. Perhaps they refer to the countries existing beyond the Black Sea and the Red Sea. The two parallel lines within the inner circle represent the Euphrates. The little rings stand for the Babylonian cities in this region.] THE TEMPLE SCHOOL The schools, in both Egypt and Babylonia, were attached to the temples and were conducted by the priests. Writing was the chief subject of instruction. It took many years of patient study to master the cuneiform symbols or the even more difficult hieroglyphics. "He who would excel in the school of the scribes," ran an ancient maxim, "must rise with the dawn." Writing was learned by imitating the examples supplied in copy- books. Some of the model letters studied by Egyptian boys of the twentieth century B.C. have come down to us. Reading, too, was an art not easy to learn. Dictionaries and grammars were written to aid the beginner. A little instruction was also provided in counting and calculating. [Illustration: AN EGYPTIAN SCRIBE (Louvre, Paris)] THE SCRIBES Having learned to read and write, the pupil was ready to enter on the coveted career of a scribe. In a community where nearly every one was illiterate, the scribes naturally held an honorable place. They conducted the correspondence of the time. When a man wished to send a letter, he had a scribe write it, signing it himself by affixing his seal. When he received a letter, he usually employed a scribe to read it to him. The scribes were also kept busy copying books on the papyrus paper or clay tablets which served as writing materials. THE TEMPLE LIBRARY Every large city of Babylonia possessed a collection of books. Several of the larger libraries have been discovered. At Nippur, in Babylonia, thirty thousand clay tablets were found. Another great collection of books was unearthed in a royal palace at Nineveh. This Assyrian library seems to have been open for the general use of the king's subjects. The Egyptians also had their libraries, usually as adjuncts to the temples, and hence under priestly control. WIDESPREAD POPULAR IGNORANCE