France, early 18th century
Wood, glass, eglomised glass
Rectangular, with double framework, this mirror is composed of a carved guilloche and gilt wood frame, flanked by plates of eglomised glass disposed beveled creating a polygonal shape on a black background emerging on plates of green background inserted in a framework in darken wood. An ornamentation with green flourished scrolls and red flowers adorns the plates with green background responding to yellow and white scrolls on dark background plates.
Flowers and scrolls in relief punctuate these plates at their extremities.
The eglomised glass
Appeared since the Roman period, the technique of the eglomisation is a particular category of the painting on glass which had a great success on a very short amount of time, at the very last of the 17th century and early 18th century before becoming fashionable again at the end of the 18th century. It consists in decorating a plate of glass on the worked reverse, with the help of gilding or different colours. The outlines of the motif are worked with an agathe pencil, then the décor is applied. It is not fixed with heat, but it is protected by another plate of glass, a layer of varnish or a layer of tint.
The process was employed numerous times at the Middle Ages and the Renaissance. However, it takes his name under a French man, Jean-Baptiste Glomy (1720 ? – 1786), framer, who made his specialty in frames adorned of plates of glass, going beyond the small measurements which usually were privileged for this technique.
The technique of glass painting, or through glass as we might say since the subject is in transparency, is indeed a huge challenge because the artist has to reverse the process of creation that is to say from the foreground to de background, or even detail elements on the background but an error is inevitable because it is impossible to correct the glass subject.
The origin of the craze under Louis XIV for the eglomised glass responds probably to the will of craftsmen to imitate the decor in tortoiseshell in the manner of André-Charles Boulle, which were particularly praised. Exceptional objects, which high prices destined to princely residences or to great lords, the décor inspired generally by ornament repositories of Jean Ier Brain or Daniel Marot.
Mirrors in the 18th century
At the end of the 15th century, in Murano Island, Italy, appeared the technique of manufacture of mercury mirrors, the only one capable of producing quality mirrors of a consistent size.
On a glass plate, a decoction of tin and warm mercury mixed was applied. This process, which was very toxic, cost the lives of many workers, and was replaced in 1837 by the technique of silverware, then definitively forbidden in 1850.
The Republic of Venice was jealously guarding this production of luxury goods and retained the monopoly. The importation of these glasses was therefore extremely expensive (30,000 gold pounds per year).
Wishing for self-sufficiency in the arts and manufactures of France, Jean-Baptiste Colbert, Minister of Finance of Louis XIV, sent spies to Murano and ordered Venetian workers to come to the Faubourg Saint-Antoine from 1665 to 1667. The latter were threatened with death by the Republic of Venice if they betrayed the secret of making mirrors.
It was at this time that the Royal Manufacture of Mirror Glass was created, which was transferred near Cherbourg in 1668, obtaining the exclusive privilege of making mirrors, thanks to the technique of “blown white glass”, the Royal Manufactory was able to compete with the Venetian productions from this date.
To obtain a flat glass, it was first blown last to form a hollow bottle called “sleeve” and then cut at the ends. The cylinder obtained was then cut lengthwise and expanded to obtain a glass sheet.
The manufactory merged in 1695 with another installed in the old castle of the lord of Coucy, in Saint Gobain in the Aisne.
The French luxury was definitely expressed with the 357 mirrors of exceptional size blown for the Galerie des Glaces.
At the end of the reign of Louis XIV, the mirror industry, headed by the Royal Manufacture of mirror mirrors, exports ice throughout Europe for an equivalent of 300,000 to 400,000 gold pounds per year. The Venetian monopoly is replaced by the French monopoly.
Good overall condition, glass with signs of wear