No people could have worked as diligently in the field of science as the Babylonians did and failed to leave important results of their investigations. "In _Geometry_ the Chaldeans made about the same progress as the Egyptians; in _Arithmetic_ more. Their notation combined the decimal and duodecimal systems. Sixty was a favorite unit, used as the hundred is by us. Scientific _Medicine_ was hindered by the belief in charms and amulets; and even _Astronomy_ was studied chiefly as a means of fortune-telling by the stars,--so that in Europe through the Middle Ages an astrologer was known as a Chaldean. However, the level plains and clear skies, as in Egypt, invited to an early study of the constellations, and some important progress was made. As we get from the Egyptians our year and months, so from the Chaldeans we get the week, with its 'day of rest for the heart,' as they called the seventh day, and the division of day and night into twelve hours each, with the subdivisions into minutes. They also invented the water clock and the sundial. They foretold eclipses, made star maps, and marked out on the heavens the apparent yearly path of the sun. The zodiacal 'signs' of our almanacs commemorate these early astronomers. Every great city had its lofty observatory and its royal astronomer; and in Babylon, in 331 B.C., Alexander the Great found a continuous series of observations running back nineteen hundred and three years. "To a degree peculiar among the ancients, the men of the Euphrates made practical use of their science. They understood the lever and pulley, and used the arch in vaulted drains and aqueducts. They invented the potter's wheel, and an excellent system of weights and measures. Their treatises on agriculture passed on their knowledge in that subject to the later Greeks and Arabs. They had surpassing skill in cutting gems, and in enameling and inlaying; and their looms produced the finest of muslins and of fleecy woolens, to which the dyer gave the most brilliant colors. In many such industries little advance has been made since, so far as results are concerned."[1] Certain unfortunate bequests were left by them. Babylonian belief in demons was handed down through the Hebrews, and in the Middle Ages took the form of the devil, with horns and a cloven foot. Their faith in magic and incantations also descended to Mediæval times, and as scientific interest superseded religious fervor, inspired men to search for the "philosopher's stone." The intensely practical turn of mind in Mesopotamia revealed itself in the literature, which was bare of imagery. Material beauty--artistic carpets, tapestries, and rugs, was developed, but for beauty of conceptions, we must turn to the Greeks.