The attraction of desire and the union of the sexes leads to the birth of the child; with the appearance of the latter the family is complete, and, with it, the type upon which the triple classification of the gods was founded. But even when we attempt to trace the composition of a single group and to assign his proper place to each of its members, the embarrassment is great. We find a single god sometimes filling, to all appearance, the _role_ of husband and father, and sometimes that of the son; or a single goddess acting at different times as the wife and daughter of one and the same god. Some of these apparent contradictions must be referred to the want of certainty in our interpretation of the inscriptions, some to the floating quality of the conceptions to which they relate. It may never, perhaps, be possible to make out a complete list, or one which shall not be obnoxious to criticism on other grounds; moreover, the historian of art has no need to enter into any such discussion, or to give the details of a nomenclature as to which Assyriologists themselves have many doubts. It suffices that he should point out the multiplicity of couples and triads, the extreme diversity of deities, and thus indicate a reason for the very peculiar aspect of the cylinders and engraved stones of Chaldaea, for the complex forms of the gods, and for the multitude of varied symbols which encumber the fields of her sculptured reliefs. Some of the figures that crowd these narrow surfaces are so fantastic that they astonish the eye as much as they pique the curiosity (see Fig. 17). [Illustration: FIG. 17.--A Chaldaean Cylinder: from Menant's _La Bible et les Cylindres Chaldeens_.] The number of divine types and the consequent difficulties of classification are increased, as in Egypt, by the fact that every important town had its local deities, deities who were its own peculiar gods. In the course of so many centuries and so many successive displacements of the political centre of gravity, the order of precedence of the Mesopotamian gods was often changed. The dominant city promoted its own gods over the heads of their fellows and modified for a time which might be long or short, the comparative importance of the Chaldaean divinities. Sin, the moon god, headed the list during the supremacy of Ur, Samas during that of Larsam. With the rise of Assyria its national god, Assur, doubtless a supreme god of the heavens, acquired an uncontested pre-eminence. It was in his name that the Assyrians subdued all Asia and shed such torrents of blood. Their wars were the wars of Assur; they were undertaken to extend his empire and to glorify his name. Hence the extreme rigour, the hideous cruelty, of the punishments inflicted by the king on his rebellious subjects; he was punishing heretics and apostates.[110]