A History of Inventions, Discoveries, and Origins. Johann Beckmann

A History of Inventions, Discoveries, and Origins - Johann Beckmann


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rel="nofollow" href="#ulink_c4f5a603-0373-507e-8537-841cdddb2f80">29 Lib. xxxiii. cap. 6.

      COLD OR DRY GILDING.

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      Dry gilding, as it is called by some workmen, is a light method of gilding, by steeping linen rags in a solution of gold, then burning them; and with a piece of cloth dipped in salt water, rubbing the ashes over silver intended to be gilt. This method requires neither much labour nor much gold, and may be employed with advantage for carved work and ornaments. It is however not durable.

      I am of opinion that this manner of gilding is a German invention, and that foreigners, at least the English, were first made acquainted with it about the end of the last century; for Robert Southwell describes it in the Philosophical Transactions for the year 1698, and says that it was known to very few goldsmiths in Germany.

      GOLD VARNISH.

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      This ingenious process, which at present is employed all over Europe in gilding wooden frames, coaches, and various articles, and which was formerly used in the preparation of the now old-fashioned leather tapestry, was invented towards the end of the 17th century. Anderson, in his Historical and chronological deduction of the Origin of Commerce, says that it was introduced into England by one Evelyn in the year 1633; and quotes, in support of this assertion, The Present State of England, printed in 1683.

      “Take shell-lac, and having freed it from the filth and bits of wood with which it is mixed, put it into a small linen bag, and wash it in pure water, till the water no longer becomes red; then take it from the bag and suffer it to dry. When it is perfectly dry, pound it very fine; because the finer it is pounded the more readily will it dissolve. Then take four parts of spirit of wine, and one of the lac, reduced, as before directed, to an impalpable powder, so that for every four pounds of spirit you may have one of lac: mix these together, and, having put them into an alembic, graduate the fire so that the lac may dissolve in the spirit. When dissolved, strain the whole through a strong piece of linen cloth; throw away what remains in the cloth, as of no use, and preserve the liquor in a glass bottle closely corked. This is the gold varnish which may be employed for gilding any kind of wood.

      “When you wish to use it, you must, in order that the work may be done with more smoothness, employ a brush made of the tail of a certain quadruped called the vari, well-known to those who sell colours for painting; and with this instrument dipped in the liquor wash gently over, three times, the wood which has been silvered. You must, however, remember every time you pass the brush over the wood to let it dry; and thus your work will be extremely beautiful, and have a resemblance to the finest gold.”

      After this invention was made known, it was not difficult to vary, by several methods, the manner of preparing it. Different receipts, therefore, have for that purpose been given in a number of books, such as Croker’s Painter, and others: and, on this account, young artists are frequently at a loss which to choose; and when a receipt is found better than another, experienced artists keep it always secret.

      With the preparation of that varnish used for gilding leather tapestry Reaumur was acquainted, and from his papers it was made known by Fougeroux de Bondaroy. The method of making the English varnish was communicated by Scarlet to Hellot, in the year 1720; and by Graham to Du Fay, in 1738. In the year 1761, Hellot gave the receipt to the Academy of Sciences at Paris, who published it in their memoirs for that year.

      If it be true, as Fougeroux says, that gilded tapestry was made above two hundred years ago, it might be worth the little trouble that such an examination would require to investigate the method used to gild it.

      FOOTNOTES


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