The ground, both inside and outside of the Dipylon Gate, was called _Cerameicus_ (“Inner” and “Outer”), its name being derived from the fine red clay which for two or three thousand years has yielded material for one of the chief branches of industrial art in Athens. The Dipylon vase was well-known as early as the eighth or seventh century B.C. Its style of decoration was geometrical, with varieties of the “key pattern.” The men and horses depicted on it are conventional and angular; and from an artistic point of view it is inferior to the earlier style. Towards the end of the seventh century it gave way to the “Phalerum” vase, which was smaller and more delicate, with some oriental features, borrowed apparently from the woven fabrics of the east. In the sixth century Attic pottery underwent great improvements, both as regards the preparation of the clay and the decoration of its surface. It became famous all over the western world, and thousands of specimens have been found in the cemeteries of Etruria, as well as in the Cerameicus and elsewhere. Instead of the figuring being in black on the red ground, the terra-cotta began to be reserved for the figures, which were thus rendered much more attractive. Though so largely used for funeral purposes the fact that so many vases have been found on the Acropolis among the ruins left by the Persian invasion shows that that was not their only use--otherwise they would not have been suitable for dedication to the gods. Many of them seem to have been placed on the grave-mound, or near it, as useful and ornamental articles, which might supply the wants of the departed. The _lecythi_, which, as already mentioned, were specially intended for funeral purposes, were generally decorated with black silhouette figures on a fine white ground. Some of the vases placed on tombs had no bottom, so that when a libation was poured into them it sank into the grave.