In the first place, the distinction between modeling and casting must be constantly kept in mind, and care must be taken not to confound the two totally different terms “mould” and “model.” That gypsum was used in modeling there can be no doubt, and it is quite possible that it may have been used to fill prepared moulds of stone, terra cotta, or other materials for the making of ectypa. There is indeed no proof of this; but as we know that moulds were made and cut in stone, into which clay was pressed, to be then withdrawn and baked for ectypa with which to adorn houses, so also it is possible that gypsum may have been used for this purpose. This, however, is merely a supposition, and the fact that none of them have ever been found in plaster renders it highly improbable. In these ectypa of clay, as well as in the impressions taken from them, there are no indications of anything like what we call a piece-mould, composed of many sections; and whenever there are under-cuttings in the ectypa, which could not be withdrawn from the mould and which would fasten them into it, these parts of the ectypa are invariably worked by hand. For instance, in the collection of Mr. Fol in Rome there are several terra cotta figures of low relief evidently stamped from a mould, which are appliqué, or fastened subsequently to the cista of which they form a part. The sutures under each figure are still visible, but they are all corrected and worked by hand after being withdrawn, and have evidently suffered in being removed from the mould. In the same collection there are several specimens of plaster reliefs, with such deep under-cuttings that they could not have been withdrawn from a single piece-mould; but all these under-cuttings are freely worked by hand, showing plainly that they were not in the stamp or mould; and it is also clear that they were afterwards worked over with fluid plaster, the edges and flats of which have not been rounded, but left as it was freely laid on by hand. It is probable that in these cases plaster was pressed into a mould in the same manner as clay, and afterwards worked up and finished. But the slightest examination will show clearly that if a mould was employed to give a general form to them, it certainly was not a piece-mould; and that they are not castings in the modern sense of the word, but only rude stamps.