The second class shows some affinities to the other in regard to the shape and the nature of the clay; but the important difference is that the vases are decorated with _painted_ subjects instead of reliefs. The subjects are painted in white outline on a brick-red glazed ground, the process being as follows: The clay, which resembles the _impasto Italico_, is first hardened by baking, and then a mixture of wax and resin and iron oxide is applied to it, and a lustre given to the surface by polishing. The pigment, a mixture of chalk and lime, is then laid on. The process can hardly be said to be Greek, and yet the subjects are purely Greek, being borrowed in part from the Greek Geometrical vases, such as sea-fights, and in part from later (Ionian) sources[2277]; we actually find representations of the Birth of Athena and the Hunt of the Calydonian Boar (Fig. 180).[2278] The shapes of the vases again are certainly local, as are the animal forms, which resemble those incised on the _bucchero_ wares. The drawing is usually crude in the extreme. It is interesting to note that on the vase from which Fig. 180 is taken the potter has painted in white an Etruscan inscription (not shown in the cut). Another vase of the same class was found in the Polledrara tomb (see Plate LVI. and p. 300 below). The method of painting in opaque pigment on a red or black ground is, it would seem, an Ionian characteristic, being found at Naukratis in the seventh century (Vol. I. p. 347), and also, as we shall see on other quasi-Ionic fabrics in Etruria. Generally speaking, the tombs _a fossa_ are not later than the middle of the seventh century; evidence of this is given by the absence of _bucchero_ proper and of Corinthian fabrics. There are, however, traces of their lingering on even down into the sixth century, as at Vulci, where Helbig mentions a tomb found in 1884 containing Corinthian vases of that date.[2279] At Corneto the latest belong to the end of the seventh century. (4) FOURTH PERIOD: CHAMBER TOMBS; ORIENTAL INFLUENCE Our fourth period, which in many respects shows a close continuity with that of the tombs _a fossa_, is nevertheless clearly defined by two circumstances: firstly, the adoption of a new type of tomb, doubtless developed out of the _fossa_, which takes the form of a large chamber, and is therefore known as _a camera_; secondly, the influence of Oriental art, concurrently with an increased influx of importations from Greece. The period covers about a century of time, from 650 to 550 B.C., and includes several of the largest and most important tombs that have been found in Etruria, which will demand more or less detailed treatment. In none, however, were any great finds of pottery made; but one of these tombs, the Grotta d’ Iside or Polledrara tomb at Vulci, contained several specimens of exceptional interest.