The difficulty of ascertaining the sources of our narrative is still further increased in no inconsiderable degree by the fact that the books of Ctesias are lost, and that Diodorus has not drawn immediately from them, but from a reproduction of Ctesias' account of Assyria. Yet the express references to the statements of Ctesias which Diodorus found in his authority, as well as fragments relating to the subject which have been elsewhere preserved, allow us to fix with tolerable accuracy what belongs to Ctesias in this narrative, and what Clitarchus, the renewer of his work, whom Diodorus had before him, has added.[16] It is Ctesias who enumerates the nations which Ninus subdued (p. 3). With him Semiramis was the daughter of a Syrian and Derceto, who throws herself into the lake of Ascalon, and is then worshipped as a goddess there.[17] To Ctesias belongs the nourishment of the child Semiramis by the doves of the goddess, her rise from the shepherd's hut to the throne of Assyria. He represents her as raising the mountain or the tomb of Ninus; he ascribes to her the building of Babylon, its mighty walls and royal citadels, the aqueducts, and the great temple of Bel. He represented her as marching to the Indus[18] and afterwards towards Media; as making gardens there and building the road over the Zagrus. He represented her as raising the mounds over the graves of her lovers;[19] he told of her sensuality, of the designs of her sons by the first marriage, and the plot of Ninyas; he recounted her end, which was as marvellous as her birth and her youth: she flew out of the palace up to heaven with a flock of doves. If the conquest of Egypt by Semiramis also belongs to Ctesias,[20] the march through Libya, and the oracle given to her in the oasis of Ammon, together with the version of her death, which rests on this oracle (she caused herself to disappear, _i.e._ put herself to death, in order to share in divine honours), belong to Clitarchus.