After what originals did the painter compose? We are quite ignorant here, and cannot specify without falling into fiction and hypothesis. Were there sketch books, representing the individual observations of the artist, taken from Nature or from great contemporary works? Or did πίνακες, tablets of wood or panels of terracotta, serve for preliminary sketches? Did a painter, as it were, design a “model” which he transferred to clay or gave to his workmen as a theme to work upon? All these questions remain unanswered. One is forced to surmise that the master signed only works on which he himself had worked, those which he designed and circulated as his latest productions, the _editio princeps_, so to speak, inscribed with his signature. But when a subject once composed was repeated in the workshop, copied with slight variations by workmen, the pottery, no matter what its commercial value, was no longer entitled to this personal certificate. [Illustration: Fig. 9. CONTEST OF MENELAOS AND PARIS. Exterior of preceding Cup.] Subjects thus composed with free repetition must be very numerous, for there is, as it were, a strong family likeness among many of them: battle scenes, banquets, gatherings of youths, games in the palæstra. Another important fact, must be stated, no obstacle was placed against plagiarism in ancient times; on the contrary, it was the spirit and essence of industrial art. We have proof of this in the terracottas as well as in the vases. Every one copies or imitates his neighbour. There is no copyright or patent for artistic property, an idea which has become the subject of legislation only in modern times. Considering the communistic way in which these Greek craftsmen lived, at a time when production was so intense, and the personal reputation of a potter might prove so great a factor in his fortune, we can readily understand how any man may have been led to protect himself against plagiarism by means of a signature which authenticated a production. A krater by Euphronios, a kylix by Douris or Brygos, might be particularly sought after by certain customers in Greece and Etruria. Why should they not be assured that they had in their hands an original work of a great master, and not a copy made by workmen or competitors? Have we not clocks signed by Boulle, and chests of drawers by Riesener, which are thus distinguished from similar objects, sometimes very beautiful, but which, without a trade-mark, do not represent original work? Such then is the sense in which we should understand the signature of a vase by Douris. He sought, devised and composed the design. And even more, his own hands carried out the painting. Let us now reflect upon the material side of the painter’s trade.