The next stage in the development of Etruscan civilisation is marked by a change in the form of the tomb. The pit is now replaced by a trench; in other words, the vertical form is exchanged for a horizontal one. Concurrently with this change the practice of inhumation becomes fairly general. This period may be regarded as extending from the eighth century B.C. to the beginning of the sixth, and is marked by the first signs of importations from Greece in the shape of Geometric pottery and bronzes. In general character it is not strongly marked off from the preceding. The great advance is in the development of art in the objects found in the tombs. Not only do we witness the first beginnings of what is destined to become the typical species of Etruscan pottery—namely, the _bucchero nero_—but towards the end of the period the Greek influence, as evidenced by finds of wheel-made vases with Geometrical decoration, or even of the so-called Proto-Corinthian type, becomes widely felt. It was no doubt largely due to the foundation of colonies in the south of Italy, such as Cumae. Altogether it is a most important period for the history of Etruscan pottery. Of Oriental influence there are at present hardly any signs, and all wheel-made vases found in these tombs are probably of Greek origin, as it does not appear that the wheel was in regular use before the middle of the sixth century.[2266] It is now necessary to turn our attention to the local hand-made varieties. And, in the first place, it is worthy of note that pottery of the Villanuova type actually survives the transition from the pit-tombs to the trenches, as is seen at Corneto, Vetulonia, and elsewhere. Probably it indicates the pottery in common use, the imported objects being only regarded as _de luxe_; or else, as Prof. Helbig suggests,[2267] the former types were preserved for religious reasons connected with burial rites, as was often the case in Roman religion. In the earlier types of pottery from the _fossa_ tombs, such as are common at Vulci, the hand-made pottery of _impasto Italico_ still continues, preserving the same shapes and the same simple linear decoration; but it is better baked, and the surface is somewhat better polished. Red wares are also found, and yellow wares with Geometrical ornaments painted in red, which are evidently local imitations of the Greek Geometrical fabrics (see below).