The ancient bronze of prehistoric days must not be confused with the metals or compounds of copper and its alloys which enabled the Greeks to produce such wonderful statues. They learned to impart hardness to copper, and wrought much delicate handiwork, much of which has perished; but enough has been spared to confirm classic history and to enable us to realize something of their conceptions of the old gods and personified hopes and aspirations. In like manner the wonderful bronzes of China and Old Japan were wrought; the metal-worker's art in those countries goes back many centuries. Some of the more delicately chiselled figures and groups were first modelled in wax upon an iron core, the mould being then formed of soft clay. When the clay was baked the wax melted, and running away through prepared outlets, left a smooth cavity into which the bronze was afterwards poured. When the metal was cold the clay would easily be broken away, and the object, at the moulding of which we often marvel, made perfect. In course of time such bronzes have been coated over with a beautiful patina of green, that natural finish which age can alone impart. It is in that state so many of the bronzes of Grecian sculptors are found, and it is covered with patina of many delightful shades that we buy the metallic curios from China and Japan. Copper for Enamels. In the days when so many beautiful ecclesiastical ornaments were fashioned, copper was the foundation used by mediæval artists as the base of their exquisite enamels. These beautiful objects are especially referred to in Chapter XVIII, where reference is also made to the enamels of Eastern countries, in the making of which brass was frequently used as the foundation. Copper has been found suitable as the groundwork upon which super-finishes have given that superiority and attractiveness associated with many of the fine arts. It was suitable for gilding over and for decorating with precious stones. Copper was also frequently used by painters, its smooth surface being regarded as an excellent material on which to work. As an example, some of the religious pictures, especially miniatures, were painted on copper, instead of on wood panels. The Brass of Commerce.