The art of glass shewing how to make all sorts of glass, crystal and enamel : likewise the making of pearls, precious stones, china and looking-glasses : to which is added, the method of painting on glass and enameling : also how to extract the colours from minerals, metals, herbs and flowers ... : illustrated with proper sculptures / written originally in French, by Mr. H. Blancourt, and now first translated into English ; with an appendix, containing exact instructions for making glass-eyes of all colours.

CHAP. CLXXXIV. To Enamel on Copper.

THO we have before touched upon the way of Enameling on Copper, yet lest the Reader should too slightly apprehend it, as not in order, or a distinct Chapter, therefore we are obliged to enter it here to avoid Imperfection.

The less use is made of this Metal in this Work the better, for the Enamel never sticks to it perfectly, but is easily scaled, divided, and broke off, which ne∣ver happens to Gold; besides, the Copper is so im∣pure, that its Fumes destroy the Beauty of the Ena∣mel so much in the Furnace, that they quite lose their Charm and Splendour by the Malignity of those Va∣pours.

Tho the Copper receives easily all thick or dark Enamels, it can't be brought so well to endure the clear and limpid; now if you would make use of these last, you must first lay a lay of Green, or Black, and thereon a Leaf of Silver to receive the Enamel suitable for that Metal mentioned in the for∣mer Chapter; so that in the main 'tis much better to make use of Silver for the Transparent Enamels, since the Copper is so apt to foul, and the charge in either much the same.

In Enameling on Copper, you must take a Plate of red Copper forged smooth, and even applying your Enamel of what Colour you desire above and under the Plate as before; then put this into the reverbera∣tory Furnace, and when it receives its polishing, draw it out.