244

ETCHING ON GLASS—GLASS-CUTTING.

gravings. His authority carries respect. But if they wereemployed on other stones, the authority which at presentdirects us, confidently alleges they did not employ them incutting glass; but he points out the mode in which thatarticle was wont to be divided, in the following terms :“ They used, for that purpose, emery, sharp-pointed instru-ments of the hardest steel, and a red hot iron, by whichthey directed the rents at their pleasure.” 5

The first mention which appears to occur of the use ofthe diamond, for this purpose, is recorded of Francis I. ofFrance, who, fond of the arts, sciences, and new inven-tions, 6 wrote the following lines with a diamond, on a paneof glass in the castle of Chambord, to let Anne de Pisseleu ,Duchess of Estampes, know that he was jealous:

Souvent femme varie,

Mai habil qui s’y fie.

It is the occasion alone that records these lines. About1652, festoons and other ornaments cut with a diamond,were made on Venetian glasses; then considered the best.George Schwanhard, the elder, was a professed adept inthat art. And since his time an artist of the name of JohnRost, of A ugsburg, cut some drinking glasses, which werepurchased by the Emperor Charles VI .

Etching on Glass. —An acid to dissolve siliceousearth was discovered as late as 1771, by the famouschymist Scheele, in sparry Jluor. It is conceived that thisart cannot be of an older date than that period; but it isalleged that an acid was discovered as early as the year1670, by the previously named Henry Schwanhard. Itbeing said that some aquafortis had dropped, by ac-cident, upon his spectacles, the glass being corroded byit, he thence leamt so to improve the liquid that he couldetch figures and writing upon glass. How he preparedthis liquid is a secret which has not been revealed.The Teulsche Akademie, before quoted, says on thissubject, that he, by the acuteness of his genius, provedthat which had been considered impossible could be ac-complished; and found out a corrosive so powerful thatthe hardest crystal glass, which had hitherto withstood theforce of the strongest spirits, was obliged to yield to it,as well as metals and stones. By these means he delineatedand etched on glass figures of men, in various situations,

s Le Veilp Die Kimst a»f glas zu malen. Nurnb. 1780, 4to. iii. p. 19.

6 Daniel Cieschichte von Frankr. viii. p. 570.