As Chaldaea, speaking broadly, made no use of stone in its buildings, the stone column or shaft was unknown to its architects; at least not a single fragment of such a thing has been found among the ruins. Here and there cylindrical piers built up of small units seem to have been employed. These are sometimes of specially moulded bricks,[251] sometimes of sandstone fragments supported by a coat of masonry. Time has separated the stones of the latter, and it is now only represented by fragments whose shape betrays their original destination. Taylor, indeed, found one of these piers still in place during his excavations at Abou-Sharein, but his sketch and description are so confused that it is quite useless to reproduce them.[252] On the other hand, Chaldaea preceded Assyria in the art of raising airy structures mainly composed of wood and metal, and by them she was led to the use of slender supports and a decoration in which grace and elegance were the most conspicuous features. We have a proof of this in a curious monument recently acquired by the British Museum. It comes from Abou-Abba, about sixteen miles south-west of Bagdad, and is in a marvellous state of preservation. Abou-Abba has been recognized as the site of the ancient Sippara, one of the oldest of Chaldaean towns. Its sanctuaries, in which the sun-god, Samas, was chiefly adored, always maintained a great importance. The monument in question is a tablet of very close-grained grey stone 11-1/3 inches long 6 inches high and, in the centre, about 3 inches thick. Its thickness increases from top to bottom. The edge is grooved. High up on the obverse there is a bas-relief, beneath this commences a long inscription which is finished on the reverse.[253] Shorter inscriptions are engraved on the field of the relief itself. The whole work--figures, inscriptions, and outer mouldings--is executed with the utmost care. The laborious solicitude with which the smallest details are carried out is to be explained by the destination of this little plaque, namely, the temple in the centre of Sippara in which a triad consisting of Sin, Samas, and Istar was the object of worship.[254] The relief itself--which we reproduce from a cast kindly presented to us by Dr. Birch--occupies rather less than half of the obverse (Fig. 71). It represents a king called Nabou-Abla-Idin, who reigned about 900, doing homage to the sun-god.[255] We shall return to this scene and its composition when the time arrives for treating Chaldaean sculpture. At present we only wish to speak of the pavilion under which the deity is enthroned upon a chair supported by two beings half man and half bull.