In the introduction to his paper on the "Chaldean Account of the Deluge," which Smith read in December, 1872, and published in 1873, he stated that the Assyrian text which he had found on Ashur-bani-pal's tablets was copied from an archetype at Erech in Lower Babylonia. This archetype was, he thought, "either written in, or translated into Semitic Babylonian, at a very early period," and although he could not assign a date to it, he adduced a number of convincing proofs in support of his opinion. The language in which he assumed the Legend to have been originally composed was known to him under the name of "Accadian," or "Akkadian," but is now called "Sumerian." Recent research has shown that his view on this point was correct on the whole. But there is satisfactory proof available to show that versions or recensions of the Legend of the Deluge and of the Epic of Gilgamish existed both in Sumerian and Babylonian, as early as B.C. 2000. The discovery has been made of a fragment of a tablet with a small portion of the Babylonian version of the Legend of the Deluge inscribed upon it, and dated in a year which is the equivalent of the 11th year of Ammisaduga, i.e. about B.C. 2000.1 And in the Museum at Philadelphia2 is preserved half of a tablet which when whole contained a complete copy of the Sumerian version of the Legend, and must have been written about the same date. The fragment of the tablet written in the reign of Ammisaduga is of special importance because the colophon shows that the tablet to which it belonged was the second of a series, and that this series was not that of the Epic of Gilgamish, and from this we learn that in B.C. 2000 the Legend of the Deluge did not form the XIth Tablet of the Epic of Gilgamish, as it did in the reign of Ashur-bani-pal, or earlier. The Sumerian version is equally important, though from another point of view, for the contents and position of the portion of it that remains on the half of the tablet mentioned above make it certain that already at this early period there were several versions of the Legend of the Deluge current in the Sumerian language. The fact is that the Legend of the Deluge was then already so old in Mesopotamia that the scribes added to or abbreviated the text at will, and treated the incidents recorded in it according to local or popular taste, tradition and prejudice. There seems to be no evidence that proves conclusively that the Sumerian version is older than the Semitic, or that the latter was translated direct from the former version. It is probable that both the Sumerians and the Semites, each in their own way, attempted to commemorate an appalling disaster of unparalleled magnitude, the knowledge of which, through tradition, was common to both peoples. It is, at all events, clear that the Sumerians regarded the Deluge as an historic event, which they were, practically, able to date, for some of their tablets contain lists of kings who reigned before the Deluge, though it must be confessed that the lengths assigned to their reigns are incredible. 

It is not too much to assume that the original event commemorated in the Legend of the Deluge was a serious and prolonged inundation or flood in Lower Babylonia, which was accompanied by great loss of life and destruction of property. The Babylonian versions state that this inundation or flood was caused by rain, but passages in some of them suggest that the effects of the rainstorm were intensified by other physical happenings connected with the earth, of a most destructive character. The Hebrews also, as we may see from the Bible, had alternative views as to the cause of the Deluge. According to one, rain fell upon the earth for forty days and forty nights (Gen. vii, 12), and according to the other the Deluge came because "all the fountains of the "great deep" were broken up, and "the flood-gates of heaven were opened" (Gen. vii, 11). The latter view suggests that the rain flood was joined by the waters of the sea. Later tradition, based partly on Babylonian and partly on Hebrew sources, asserts in the "Cave of Treasures"3 that when Noah had entered the Ark and the door was shut, "the sluices of heaven were opened, and the deeps were rent asunder," and "that the Ocean, that great sea that surroundeth the whole world, vomited its waters, and the sluices of heaven being opened, and the deeps of the earth being rent asunder, the storehouses of the winds were opened, and the whirlwinds broke loose, and the Ocean roared and poured out its waters in floods." The ark was steered over the waters by an angel who acted as pilot, and when that had come to rest on the mountains of Kardô (Armenia) "God commanded the waters and they separated from each other. The waters that had been above ascended to their place above the heavens, whence they had come; and the waters that had come up from under the earth returned to the lower deep; and the waters that were from the Ocean returned into it" (Brit. Mus. MS. Orient. No. 25,875, fol. 17b, col. 1 and fol. 18a, cols. 1 and 2). Many authorities seeking to find a foundation of fact for the Legend of the Deluge in Mesopotamia have assumed that the rain flood was accompanied either by an earthquake or a tidal wave, or by both. There is no doubt that the cities of Lower Babylonia were nearer the sea in the Sumerian Period than they are at the present time, and it is a generally accepted view that the head of the Persian Gulf lay further to the north at that time. A cyclone coupled with a tidal wave is a sufficient base for any of the forms of the Legend now known.