GILDING. 



reader to the article GOLD; but the other 

 two substances being prepared by the 

 gilder himself, may be with propriety 

 described here. The amalgam of gold 

 is made, by heating in a crucible some 

 pure quicksilver ; and when it is nearly 

 boiling, adding to it about a sixth of its 

 weight of fine gold in thin plates, heated 

 red hot ; the mixture, after being kept 

 hot for a few minutes, becomes of a 

 perfectly homogeneous consistence, and 

 may then be allowed to cool : when cold, 

 it is to be put in a piece of soft leather, 

 and, by gradual pressure, the fluid part 

 of the amalgam, consisting almost wholly 

 of mercury, may be forced through the 

 pores of the leather, while the gold com- 

 bined with about twice its weight of mer- 

 cury will remain behind, forming a yel- 

 lowish silvery mass of about the consis- 

 tency of soft butter. This, after being 

 bruised in a mortar, or shaken in a strong 

 phial, with repeated portions of salt and 

 water, till the water ceases to be fouled 

 by it, is fit for use, and may be kept for 

 any length of time without injury in a 

 corked phial. It is of essential impor- 

 tance that the materials of this amalgam, 

 and especially the mercury, should be 

 perfectly pure, as the least portion of 

 lead or bismuth would very materially 

 injure the beauty of the gilding, by de- 

 teriorating the colour of the gold, and 

 filling it with black specks ; on this ac- 

 count no mercury ought to be employed, 

 that has not been procured by distillation 

 from the red precipitate (nitrous red ox- 

 ide of mercury) either alone or mixed 

 with a little charcoal powder. 



Gold is prepared in three different 

 ways. The first and simplest is, to put 

 into a glass or earthen mortar some gold- 

 leaf, with a little honey or thick gum-wa- 

 ter, and grind the mixture for a consider- 

 able time, till the gold is reduced to ex- 

 tremely minute fragments ; when this is 

 done, a little warm water will wash out 

 the honey or gum, leaving the gold be- 

 hind in a flaky pulverulent state. A less 

 tedious and more effectual way of com- 

 minuting the gold is, to dissolve it in 

 nitre-muriate acid, and then precipitate it 

 with a piece of copper: the precipitate, 

 after being digested in distilled vinegar, 

 and then washed in water and dried, is 

 in the form of a very fine powder, and 

 both works better, and is easier to.burnish, 

 than the ground leaf-gold. The finest 

 ground gold is however produced by 

 heating very gradually the gold amalgam 

 in an open earthen vessel, and continu- 

 ing the fire till the whole of the mercury 



is evaporated, taking care that the amal- 

 gam shall be constantly stirred with a 

 piece of glass, rod, or tobacco-pipe, in 

 order to prevent the particles of gold 

 from adhering as the mercury flies off. 

 When the mercury is completely evapo- 

 rated, the residual gold being then ground 

 in a Wedgewood-ware mortar, with a 

 little water, and afterwards dried, it is 

 fit for use. 



Gilding is performed either with or 

 without heat. By the first of these me- 

 thods those substances are gilt, . which 

 are not liable to alteration by exposure 

 to a moderate heat, such as metals, and 

 sometimes glass and porcelain : the se- 

 cond method is practised with those sub- 

 stances, such as wood, paper, lead, silk, 

 lacquered and japanned ware, &c. which 

 would be injured, and even destroyed, at 

 the temperature requisite for gilding the 

 former. The last of these methods, be- 

 ing the simplest, shall be first described, 

 and we shall begin with the art of gilding 

 on wood. 



There are two methods for gilding on 

 wood, namely, oil gilding and burnished 

 gilding Oil gilding is thus performed : 

 the wood must first be covered, or prim- 

 ed, with two or three coatings of boiled 

 linseed oil and white-lead, in order to 

 fill up the pores, and to conceal the irre- 

 gularities of the surface occasioned by 

 the veins in the wood. When the prim- 

 ' ing is quite dry, a thin coat of gold-size 

 must be laid on. This is prepared by 

 grinding together some strongly calcined 

 red ochre, with the thickest drying oil 

 that can be procured, and the older the 

 better : that it may work freely, it is to 

 be mixed, previously to being' used, with 

 a little oil of turpentine, till it is brought 

 to a proper consistence. If the gold-size 

 is good, it will be sufficiently dry in 

 twelve hours, more or less, to allow the 

 artist to proceed to the last part of the 

 process, which is the application of the 

 gold. For this purpose a leaf of gold is 

 spread on the cushion (formed by a few 

 folds of flannel secured on a piece of 

 wood, about eight inches square, by a 

 tight covering of leather), and is cut into 

 strips of a proper size by a blunt pallet- 

 knife : each' strip being then taken up on 

 the point of a fine brush is applied to 

 the part intended to be gilded, and is 

 then gently pressed dovvn by a ball of 

 soft cotton ; the gold immediately ad- 

 heres to the sticky surface of the siz/, 

 and after a few minutes the dexterous ap- 

 plication of a large camel's hair brush 

 sweeps away the loose purticles of the 



