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though extended over a much larger surface, wasthickest, owing to the difference in its specificgravity. In practice, the gold leaf is never extendedbeyond the ■j-sinnro^' 1 P art an i n °h i n thickness.
The late Dr. Dee erroneously states, that the goldused in gold-beating ought to be of the finest stand-ard. Alloy, he adds, hardens gold, and renders itless malleable ; so that the fraudulent tradesman whoshould attempt to debase the gold would exposehimself to much greater loss in the operation than hecould derive profit from the alloy. From this state-ment it might be inferred that nothing but fineor perfectly pure gold is used by the gold-beater,whereas, in point of fact, it is alloyed in various ways,according to the colour required. Indeed, it is notuncommonly supposed, among the workmen employedin the business, that fine gold is incapable of beingreduced to thin leaves ; but this also is an error.It is simply objectionable for commercial purposes,on account of its greater cost, and also on account ofthe adhesion which takes place when one part of aleaf of fine gold touches another, thus causing a wasteof labour by the leaves being spoiled. For work,however, which is to be exposed to the weather, finegold is the best, being more durable, and not liableto tarnish or change colour.
A London gold-beater, E. S. Marshall, exhibitedspecimens of gold-leaf at the Great Exhibition of1861, for which the prize medal was awarded to him.The specimens were twelve in number, and embraceda regular gradation in colour from red to nearlywhite—namely, red, pale red, extra deep, deep, orange,lemon, deep pale, pale, pale pale, deep party, party,and fine gold. The deeper colours were alloyedwith from 12 to 16 grains of copper per oz., but nosilver, since any admixture of this metal with so largea quantity of copper would considerably impair themalleability of the alloy; the medium colours con-tained from 12 to 20 grains of silver, with from 6 to8 grains of copper to the oz.; and, lastly, the palerleaves contained from 2 to no less than 20 penny-weights of silver to the oz., but no copper, for thesame reason that silver was omitted in the red ordeep-coloured golds.
The process of gold-beating is purely a mechanicaloperation, but involving as it does one of the mostimportant applications of this precious metal, it willbe necessary to give a short account of it. The firstoperation is the casting of the metal into ingots. Forthis purpose the gold, either pure or alloyed, accordingto the colour desired, is melted in a crucible at ahigher temperature than is simply necessary to fuseit, by which its malleability is improved. It is thenpoured into moulds previously heated and greasedon the inside, and cast into flat oblong ingots, eachabout three-fourths of an inch wide, and weighing 2ozs. The ingots, when taken from the moulds, areannealed in hot ashes, which cleanse them from greaseand increase the malleability of the gold. When theingot is cold, the French gold-beaters hammer it outto the thickness of one-sixth of an inch, and exposeit at the same time to repeated annealings ; but thisoperation, termed the forging , is omitted by the
English gold-beaters. The next process is the lamin-ation, which consists in repeatedly passing the ingotbetween two rollers of polished steel, graduallybrought closer together, until it is formed into ariband of 1J inch in width, and 10 feet in length,to the oz. By this means the ingot is spread outto a surface of 960 square inches of the thicknessof rather more than of an inch. The nextoperation is the beating, for which purpose theriband of gold, after being annealed or softenedin the fire, is carefully divided with compasses andcut up into pieces 1 inch square, each weighingabout 6 grains; about 160 of these are placed bymeans of wooden pliers between the leaves of acutch, which formerly consisted of a packet of finecalf-skin vellum, but now it is usual to employa tough paper manufactured in France . A case ofstrong parchment, open at both ends, is drawn overthe cutch, and this is inclosed in a second similarcase at right angles to the first, so as to cover theedges which the first had left exposed The cutchis then beaten with a 17 lb. hammer, upon a smoothblock of black marble, supported on a strong bench,and surrounded on three sides by a wooden ledge,while the front is left open, and has a leathern apronattached to it, to preserve any fragments of gold thatmay fall out of the packet. The hammer is short-handled, and is wielded by the workman with onehand, while with the other he occasionally turns thepacket over, to distribute the force equally. Theelasticity of the packet causes the hammer to rebound,and lightens the labour of the operator. At intervalsthe packet is taken up, and bent or rolled betweenthe hands, to overcome any slight adhesion betweenthe leaves and the interposed paper or vellum; or it istaken to pieces to examine the state of the gold, and toshift the central leaves to the outside, and vice versa.
When the gold plates of 1 inch side are thusspread out into 4-inch squares, or to nearly the sizeof the leaves of the cutch, which generally requiresabout twenty minutes’ beating, the packet is opened,and each leaf of gold is taken out, and cut with aknife into four equal squares, thus increasing the 150pieces to 600 of nearly the same size as at first.These are put between the leaves of another tool,called a shoder, made of gold-beater's skin. This sub-stance is the ceecum of the ox, which is first doubled,then prepared with solutions of alum, isinglass,white of egg, &c., and after being beaten betweenfolds of paper to expel the grease, is finally pressedand dried. The shoder is inclosed in parchment andbeaten as before, but with a smaller hammer, about9 or 10 lbs. weight, till the squares of gold are againextended to nearly the size of the skins. The shoderrequires about two hours’ beating for this purpose.During this period the packet must be often folded,to render the gold as loose as possible betweenthe membranes. As all the leaves do not spreadquite equally, the shoder is beaten upon after themore expanded leaves have reached the edges, theeffect of which is, that these come out of the edgesin the shape of dust, and this allows time for thesmaller leaves to reach the full size of the shoder.