_Greek._--The paste of these vases is tender, easily scratched or cut with a knife, remarkably fine and homogeneous, but of loose texture. When broken, it exhibits a dull opaque color, more or less yellow, red or grey. It is composed of silica, alumina, carbonate of lime, magnesia and oxide of iron. The color depends on the proportions in which these elements are mixed; the paler parts containing more lime, the red more iron. The exterior coating is composed of a particular kind of clay, which seems to be a kind of yellow or red ochre, reduced to a very fine paste, mixed with some glutinous or oily substance, and laid on with a brush; great difference is observable in the pastes of vases coming from widely separated localities, owing either to their composition or baking. The paste of the early vases of Athens and Melos is of a very pale red; that of vases of the Doric or Corinthian style is of a pale lemon color. At the best period of the art, the paste is of a warm orange red; but Lucanian and Apulian vases are of a paler tone. The Etruscan painted vases of all ages are of a pale red tone, with a much greater proportion of white, which appears to be owing to the greater proportion of chalk used in preparing the paste. The earliest vases were made with the hand, while those of a later period were made with the wheel; the wheel, however, is a very early invention. Among the Egyptians and Greeks it was a low, circular table, turned with the foot. Representations of a potter turning the wheel with his foot, occur on painted vases of an early date. With this simple wheel the Greeks effected wonders, producing shapes still unrivalled in beauty.