The chronological notice of Nabonidus thus serves to confirm, so far as its evidence goes, the general accuracy of the date assigned to the First Dynasty. In the case of the Second Dynasty we obtain an equally striking confirmation, when we examine the only available reference to the period of one of its kings which is found in the record of a later ruler. The passage in question occurs upon a boundary-stone preserved in the University Museum of Pennsylvania, referring to events which took place in the fourth year of Enlil-nadin-apli.[59] In the text engraved upon the stone it is stated that 696 years separated Gulkishar (the sixth king of the Second Dynasty) from Nebuchadnezzar, who is of course to be identified with Nebuchadnezzar I., the immediate predecessor of Enlil-nadin-apli upon the throne of Babylon. Now we know from the "Synchronistic History" that Nebuchadnezzar I. was the contemporary of Ashur-rêsh-ishi, the father of Tiglath-pileser I., and if we can establish independently the date of the latter's accession, we obtain approximate dates for Nebuchadnezzar and consequently for Gulkishar. In his inscription on the rock at Bavian Sennacherib tells us that 418 years elapsed between the defeat of Tiglath-pileser I. by Marduk-nadin-akhê and his own conquest of Babylon in 689 B.C.[60] Tiglath-pileser was therefore reigning in 1107 B.C., and we know from his Cylinder-inscription that this year was not among the first five of his reign; on this evidence the beginning of his reign has been assigned approximately to 1120 B.C. Nebuchadnezzar I., the contemporary of Tiglath-pileser's father, may thus have come to the throne at about 1140 B.C.; and, by adding the 696 years to this date, we obtain an approximate date of 1836 B.C. as falling within the reign of Gulkishar of the Second Dynasty. This date supports the figures of the Kings' List, according to which Gulkishar would have been reigning from about 1876 to 1822 B.C. But it should be noted that the period of 696 years upon the boundary-stone, though it has an appearance of great accuracy, was probably derived from a round number; for the stone refers to events which took place in Enlil-nadin-apli's fourth year, and the number 696 may have been based upon the estimate that seven hundred years separated Enlil-nadin-apli's reign from that of Gulkishar. It is thus probable that the reference should not be regarded as more than a rough indication of the belief that a portion of Gulkishar's reign fell within the second half of the nineteenth century. But, even on this lower estimate of the figure's accuracy, its agreement with our scheme is equally striking.