The next tolerably certain date is that of Ur-ea, and his son Dungi, two kings of the old Accadian race, who reigned at Ur over the united kingdoms of Sumir and Accad. They were great builders and restorers of temples, and have left numerous traces of their existence in the monuments both at Ur, and at Larsam, Sirgalla, Erech, and other ancient cities. Among other relics of these kings there is in the British Museum the signet-cylinder of Ur-ea himself, on which is engraved the Moon-God, the patron deity of Ur, with the king and priests worshipping him. The date of Ur-ea is ascertained as follows--Nabonidus, the last king of Babylon, 550 B.C., was a great restorer of the old temples, and, as Professor Sayce says, "a zealous antiquarian who busied himself much with the disinterment of the memorial cylinders which their founders and restorers had buried beneath their foundations." The results of his discoveries he recorded on special cylinders for the information of posterity, which have fortunately been preserved. Among others he restored the Sun-temple at Larsam, in which he found intact in its chamber under the corner-stone, a cylinder of King Hummurabi or Khammuragas, stating that the temple was commenced by Ur-ea and finished by his son Dungi, 700 years before his time. Hummurabi was a well-known historical king who expelled the Elamites, and made Babylon for the first time the capital of Chaldæa, about 2000 B.C. The date of Ur-ea cannot therefore be far from 2700 B.C. The same fortunate circumstance of the habit, by kings who built or restored famous temples, of laying the foundation-stone, such as our royal personages often do at the present day, and depositing under it, in a secure chamber, a cylinder recording the fact, has given us a still more ancient date, that of Sharrukin or Sargon I. of Agade. The same Nabonidus repaired the great Sun-temple of Sippar, and he says "that having dug deep in its foundations for the cylinders of the founder, the Sun-god suffered him to behold the foundation cylinder of Naram-Sin, son of Sharrukin or (Sargon I.), which for three thousand and two hundred years none of the kings who lived before him had seen." This gives 3750 B.C. as the date of Naram-Sin, or, allowing for the long reign of Sargon I., about 3800 B.C. as the date of that monarch. This discovery revolutionized the accepted ideas of Chaldæan chronology, and carried it back at one stroke 1000 years before the date of Ur-ea, making it contemporary with the fourth Egyptian dynasty who built the great Pyramids. The evidence is not so conclusive as in the case of Egypt, where the lists of Manetho give us the whole series of successive kings and dynasties, a great majority of which are confirmed by contemporary records and monuments. The date of Sargon I. rests mainly on the authority of Nabonidus, who lived more than 3000 years later, and may have been mistaken, but he was in the best position to consult