Besides, let us look at the practical difficulty in this process. After the moulds were made and the wax cast into them, as Mr. Perkins interprets Pliny to mean, we have still only wax impressions, and not plaster castings. And how were they got out of the mould after they were cast? We, in modern times, have learned no method of doing this; we should be obliged first to make the mould in plaster, then to make a cast in plaster in that mould, then on that cast to make a piece-mould with sections to take apart,—an elaborate process; and then we could get a wax cast, but not before. The fact that the cast mentioned by Pliny (supposing he means a cast) is in wax not only involves quadruple labor and skill on the part of the caster, but makes the process impossible, or next to impossible, if it were simply as he is supposed to describe it. If the cast were in plaster, it would resist, so that the mould could be broken off from it in bits; but with wax this would be entirely impracticable. Let us still further consider the phrase “ceraque in eam formam gypsi infusa emendare instituit.” What does “cera in eam formam infusa” mean? Simply to cover or spread wax (or color) over that model; just as Ovid says “infundere ceram tabellis,” to spread wax over the tablets, not to pour wax into the tablets, for that was impossible, they being flat surfaces, nor to cast them. Again, Pliny does not say that Lysistratus introduced the practice of spreading wax over a core, or of pouring wax into a form, or casting; but only of improving the likenesses, or working them up in the wax after it was spread over the plaster: “instituit emendare,” he says, not “instituit infundere.” “Formam” here has not the signification of mould, but of model or image. Undoubtedly the term “forma” in Latin was used to signify a mould as well as a cast, or a model, or a form; and in this respect it had the same ambiguity that the corresponding terms “mould” and “form” have in English. A “form” is a seat, as well as a shape and a ceremony, and “mould” is constantly, though improperly, used to indicate a model or the thing moulded, as well as the real mould in which it is cast; the phrases “to model” and “to mould” are often synonymous in meaning. So “forma” was sometimes employed in its primary significance of figure, shape, and configuration, as when Quinctilian says, “Eadem cera aliæ atque aliæ formæ duci solent,”—various shapes may be given to the same wax; sometimes in the sense of image, as when Cicero speaks of “formæ clarissimorum,” the images of distinguished men; sometimes to mean a model or shape over which a thing is wrought, as a shoemaker’s last,—“Si scalpra et formas non sutor emat,” as Horace says; and sometimes as indicating a hollow mould in which bronze is cast, as when Pliny says, “Ex iis [silicibus] formæ fiunt, in quibus æra funduntur,”—from these pebbles moulds are made, in which brass is cast. But when he uses it in this last sense, it will be observed,