Gold is deposited on articles required to be gilt by precisely the same method of operation, except that the solution is the cyanide of potassium and gold. In the silver deposit the solution is used cold, but in that of the gold, it is heated to about 100 degrees Fahrenheit. In some cases, such as the gilding of buttons, or small articles of jewellery, a few minutes are only necessary to give them the required coating of pure gold. In some of the show rooms of the factories are many little slips of holly and other plants coated, some with pure gold, some with copper, and some with silver; all exhibiting the minute details of leaf and fibre with extraordinary beauty. It is only necessary to dip a leaf or twig into a solution of phosphorus and immediately afterwards in the deposit tank, when it is instantly covered with metal. Even butterflies and insects are often coated with gold in the same manner.

The finishing processes of the electro manufacture are equally important with those already described. The raw articles are first rubbed with what are technically called "scratch brushes," made of brass wire, which soon give a metallic appearance to the plate. Next comes the "burnishing," which is effected chiefly by pieces of bloodstone or agate, and the burnisher is usually a female. With her burnisher, which has been moistened, she rubs over every part of the article to be burnished, using a considerable deal of force in the operation, by which means a surface of great brilliancy is soon produced.

Besides the mere coating of articles with gold or silver by means of electro-galvanism, the same agency is capable of manufacturing a gold or silver article entirely. The process is somewhat complicated in description, but easy enough to the manufacturer; the design being

wrought in wax by the modeller, the wax model is wrought in lead; from this a brass pattern is cast, and from this model or pattern a second mould is made of a peculiar elastic composition, formed of glue and India Rubber. The pattern is enclosed in a frame, and the melted composition poured into it; when cold, this composition is moved from the pattern in one piece. Then from this mould a model or pattern is cast in a composition of wax, suet, or phosphorus; and the model thus produced forms a surface on which electro deposition is to take place. The composition model is next transferred to the copper deposit room in the manufactory, and afterwards put into the tank. In the tank is a solution of sulphate of copper, and in an adjoining vessel is another solution of nitrate of silver. The phosphorus contained in the composition induces the deposition of a thin layer of silver from the nitrate solution, the model is then immersed in the solution of sulphate of copper.

The galvanic current acting in the manner before described decomposes the metallic solution, and precipitates the liberated copper on the surface of the model, or rather on the slight silver layer already covering it, coating it with a layer of metallic copper, more or less thick, according to the circumstances under which the operation is conducted. When the copper deposition is properly completed, the wax composition is melted out, leaving a mere copper shell, the interior of which is an exact mould of exterior of the wax model. This copper mould, after a further preparation, is immersed in the gold or silver solution, the interior being prepared for the reception of the deposited metal, but the exterior protected from it by a resisting composition; then, by the agency before described, the silver is deposited in the copper shell or mould to thickness that

any

may be required. This being completed, the copper is removed by the action of an acid, which gradually eats away without injuring the silver, and the result is, the production of a pure and solid ornament or article of table plate, having not a single particle in or about it but what has been deposited from the liquid solution in the tank.

In the whole of these processes, there is a great deal to speculate on and admire. There is a rare union of taste, chemical knowledge, mechanical nicety, and attentive care. Many of the details are altogether out of the common run of manufacturing industry, and the whole is one of those triumphs of science which tend so powerfully to exalt the manufactures of this country in the eyes of foreigners.

Manufacture of Buttons.

There are various kinds of buttons, forming distinct trades, such as those of horn, leather, bone, or wood; but the most durable and ornamental buttons are made of various metals, polished or covered with a thin wash of some more valuable metal, as gold or silver.

The most curious part of horn button-making consists in a simple machine or lathe by which the material is cut into a round form. It is represented in the cut, and consists of two thin knives on a pointed axis, the whole of which revolves and then cuts the circular disc;

the holes are afterwards drilled in a similar manner by a lathe with four axes, turning from a wheel which is put in motion by the foot of the workman.

Metallic buttons are cast in moulds, or cut by a fly press. They are generally formed of an inferior kind of brass, pewter, or other metallic composition; the shanks are made of brass or iron wire, generally by hand, and the formation of which is a distinct trade. The buttons are made by casting them round the shanks. For this purpose the

workman has a pattern in metal, consisting of a great number of circular buttons connected together in one plane by very small bars from one to the next, and the pattern contains from four to twelve design patterns of the same size. An impression from this pattern is taken in sand in the usual manner, and shanks are pressed into the sand in the centre of each impression; the part which is to enter the metal being left projecting above the surface of the sand. The metal is then poured upon the moulds, and the buttons are said to be

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rough cast. They are cleansed from the sand by brushing, and then turned in a lathe to render them perfectly circular and clean.

Gilt buttons are stamped out from copper from laminated plates by a fly press which cuts them out at one stroke. The circular pieces are called blanks, and having been stamped with the maker's name, the shanks are soldered in. The burnishing is performed by a point of bloodstone applied to the button as it revolves in a lathe. In gilding them a great number are put into an earthen pan with a certain quantity of gold amalgamated with mercury, and then as much aquafortis as will wet the buttons all over is thrown in, and they are then stirred with a brush till the acid, by its affinity with the copper, carries the amalgama to every part of its surface, covering it with the appearance of silver. When this is perfected, the acid is washed away with clean water. The mercury is afterwards evaporated by a process called drying off, once inflicting very serious effects on the health of the workman, owing to their inhaling large quantities of mercury. This is, however, now obviated, in a great degree, by the use of an apparatus which carries off the fumes of the mercury from the buttons, by means of a flue which discharges itself into water, and there condenses the mercury.

Many improvements have been made in the manufacture of buttons of late years. The shanks are made by machinery, and some kinds of buttons are made head and shank out of one piece stamped and polished by a French process.