GILDING. 



nished, taking care only to interpose a 

 pieee of very thin paper between the gold 

 and burnisher. If the varnish is very 

 good, this is the best method of gilding 1 ' 

 glass, as the gold is thus fixed on more 

 evenly than in any other way: it often 

 happens, however, when the varnish 

 is but indifferent, that by repeated wash- 

 ing the gold soon wears off: on this ac- 

 count, the practice of burning it in is 

 sometimes had recourse to. 



For this purpose some gold powder is 

 tempered with borax, and in this state ap- 

 plied to the clean surface of the glass, 

 with a clean camel's hair pencil: when 

 quite dry, the glass is put in a stove heat- 

 ed to about the temperature of an anneal- 

 ingoven, the gum burns off, and the borax 

 by vitrifying cements the gold with great 

 firmness to ihe glass; after which it may 

 be burnisl/ed. The gilding upon porce- 

 lain is in like manner fixed by fire and 

 borax ; and this kind of ware being nei- 

 ther transparent nor liable to soften, and 

 thus injure its form in a low red heat, is 

 free from the risk and injury, which 

 the finer and more fusible kinds of 

 glass are apt to sustain from such treat- 

 ment. 



All the methods of gilding hitherto 

 described resemble each other, by being 

 accomplished by means of some adhesive 

 medium; this,hovvever,is not the case with 

 gilding upon metals; the gold is brought 

 into immediate contact with the other me- 

 tal, and they both remain firmly united 

 merely by the attraction of adhesion sub- 

 sisting between them. The simplest of 

 all the kinds of gilding on metal, and 

 which strikingly demonstrates the power 

 of the affinity of adhesion, is one which is 

 sometimes practised on plane surfaces of 

 copper and iron, with considerable suc- 

 cess. The metal, being previously polish- 

 ed, is heated to about the temperature of 

 melted lead, and covered with a double 

 layer of gold leaf: by the cautious appli- 

 cation of a blood stone burnisher, applied 

 gently at first, and increasing the force of 

 the pressure by degrees, the surface of 

 the gold and copper are brought to touch 

 each other in almost every point, and then 

 adhere with a force proportionate to the 

 completeness of the contact. The first 

 layer being thus burnished down, a se- 

 cond is made to adhere in the same man- 

 ner, and sometimes a third, if the gilding 

 is intended to be very solid. The objec- 

 tion to this kind of gilding is its tedious- 

 ness, and the almost impossibility of using 

 a sufficient pressure without injuring the 

 evenness of the gilded surface : where 



these objections do not apply, there can- 

 not be a more effectual mode of gilding, 

 as is evident from the manufacture of gilt 

 silver and copper wire. The bar, before 

 it is committed to the wire-drawer, is 

 plated with gold, by having several plates 

 of gold successively burnished down upon 

 it,and being thensubjected to the stronger 

 compression which takes place in wire- 

 drawing, the gold and the other metal be- 

 come so perfectly united as to form in a 

 manner but one substance. 



The most usual method of covering the 

 face of a metal with gold is by means of 

 an amalgam, or, as it is technically called, 

 water-gilding. If the metal to be gilt is 

 silver, the best method of proceeding is, 

 first to soak it in warm dilute muriatic 

 acid.that the surface may be rendered per- 

 fectly clean ; it must then be washed in 

 clean water, changed two or three times, 

 to get rid of the whole of the acid : be- 

 ing afterwards dried, and made mode- 

 rately warm, a little gold amalgam, also 

 warm, is to be carefully and evenly spread 

 upon the silver, to which it will immedi- 

 ately adhere: when this is completed, 

 the piece is placed upon a convenient 

 support over a charcoal fire, and while 

 the mercury is evaporating, if any specks 

 or places appear, which have escaped 

 the amalgam, a small piece is to be laid 

 on and spread with a brush, to supply the 

 deficiency, without removing the ai-ticle 

 from the fire. After a time, the whole 

 of the mercury will be driven off, and 

 the piece, after cooling, being accurate- 

 ly examined, will be found to be entire- 

 ly covered with a thin coating of pale 

 dull gold. The small roughnesses, and 

 loosely -adhering particles, are now to be 

 removed with a scratch -brush, which is 

 made of some extraordinary fine brass 

 wire, bound together into a tuft ; by it 

 the surface is rendered perfectly smooth 

 and bright; but it still remains of a 

 pale yellowish colour : this defect is 

 next removed by warming the piece, and 

 smearing it over with gilders' wax, a 

 composition of bees' wax, red ochre, 

 verdigris, and green vitriol or alum. 

 1 The wax being burnt over a charcoal 

 fire, and the piece quenched in urine, 

 the colour of the gilding will be found 

 to be much heightened ; if it is not suffi- 

 ciently so, the application of a succeed- 

 ing one will complete the desired ef- 

 fect, after which the work may be burn-, 

 ished or not, according to the taste 

 of the artist. Instead of the common 

 gilders' wax, a mixture of equal parts of 

 nitre, sal-ammoniae, green vitrol, and 



