be different reasons for this somewhat late development of such an important process. The early brass works were chiefly concerned with the manufacture of wire and battery goods such as pans and kettles. Moreover, special sand is necessary for casting, and this may not have been easily obtainable, while the making of moulds is a complicated operation requiring much ingenuity and skill. The first account of casting is given in the last decade of the seventeenth century, and deals with the manufacture of thimbles at a works at Islington. A special kind of sand, which, it was said, was only obtained at Highgate, was mixed with red ochre, and the patterns were embedded in it so as to form the moulds. Since thimbles are hollow, it was necessary to insert supports or cores, and round these the metal was poured. When the metal was cold the castings were taken out and separated from one another with greasy shears, the cores being extracted from the thimbles by boys, who used pointed pieces of iron for this operation.1 About six gross were made at one casting. At the beginning of the eighteenth century there were at least two brassfounders in Birmingham, but by the second half of the century the process of casting was well known, and innumerable articles were manufactured in this way. The town was particularly adapted for this process, since in its vicinity there was a good supply of the special sand necessary for casting. In the last thirty years of the eighteenth century the new process of stamping came into use, and it has played a very large part in the brass and copper industries ever since. It was the setting up of rolling mills, which received a great impetus from the invention of the steam engine, that opened up the way for the extensive use of this process, and in fact gave rise to the stamped brassfoundry trade. John Pickering, a gilt toymaker of London, was the first to see the possibility of stamping certain articles from sheet metal, and in 1769 he obtained a patent 3 for a limited application of this new process. He showed how designs for coffin furniture and ornaments for coaches, carriages and furniture could be 'Houghton, Collections, ut supra, No. 260, July 23, 1697. • Indenture between Thos. Orme, toymaker, and Henry Carver and Walter Tippin, brassfounders, 1715 (Birmingham Ref. Lib. 297287). Patents, 1769, 920. stamped instead of being laboriously engraved.1 For this purpose he invented a machine consisting of a moving weight or hammer, faced with soft metal, which was to move between two rods. The hammer was to be allowed to fall on the sheet metal, which was laid on a striking block over a fixed die or raised model of the pattern desired, and by this means the die would be forced into the sheet metal, and so the impression would be obtained. This was only the first use of a very important process, the possibilities of which were recognised by Richard Ford of Birmingham, when, a few months later, he applied the principle to the making of such articles as saucepans, warming pans, basins, ladles, and plate covers. His method was to use "two implements called dyes placed under the hammer of a stamp or screw of a press, the one being concave, the other convex, which by the pressure of the hammer or screw forced into the dye, the shape or the form of the thing designed is accomplished." A few years later another Birmingham man, John Smith, applied the process to the manufacture of buttons, and so revolutionised the trade, for up to this time buttonmaking had been a tedious business, since the designs on them were laboriously engraved. Great economy resulted from his invention, for the stamp gave the form to the button, and the press the objects represented on it.3 Two other Birmingham manufacturers, John Marston, brassfounder, and Samuel Bellamy, engraver and die sinker, are associated with the new process, and in 1777 they obtained a patent for stamping hat and cloak pins, and various ornaments for furniture. Finally, in 1779, William Bell invented a new way "of affixing impressions from dies upon gold, silver, or mettals by means of rolling cylinders, on which such dies are engraved, which would be to the great benefit of trade, particularly to the buckle, button and toy manufactories." 5 It is obvious, then, that the new process 1 In 1759, however, a Birmingham man called Bedford had invented a new way of "impressing in imitation of ingraving upon varnish laid upon copper, iron, paper and other bodies." His method was to engrave designs or decorations on copper, and then to take off the impression with very thin rolled lead. The material on which the design was to be made was covered with varnish, and on this surface the lead was impressed (Patents, 1759, 737). • Ibid., 1777, 1165. 'Patents, 1769, 935. Ibid., 1779, 1242. Ibid., 1770, 989. would have a very wide application, and would be used for manufacturing many household and other articles in copper and brass. Another process which came into common use towards the end of the eighteenth century is "plating," and this too was of particular importance for the button, buckle and toy trades. The credit for the invention is usually given to Thomas Bolsover, of Sheffield, who, in 1743, showed how silver could be plated over copper in the manufacture of buttons, snuff boxes and other light articles. This idea, however, was not a commercial success in his life time, but another Sheffield manufacturer, Joseph Hancock, took it up later on and employed it in the manufacture of candlesticks, teapots and such like articles.1 Perhaps allied to this new method, which came to be used extensively in the button, buckle and toy trades, was one which John Bootie patented in 1768, and which dealt with the tinning of copper and brass vessels such as ships, kettles and kitchen furniture." Even this invention did not eliminate the danger from using kitchen vessels of copper and brass, and several years after this the fear of poisoning was a very real one. However, in 1790 William Collins of Lambeth and Charles Wyatt of Birmingham claimed to have discovered " a new article of trade and commerce, being an improvement of copper sheets or plates and brass sheets or plates, by covering and combining them with a metallic or semi-metallic substance, which covering will prevent all noxious effects from these metals when used for culinary purposes, or for containing or carrying water.” 4 3 There are, of course, many minor processes in the production of brass and copper goods, but those mentioned may be taken to be the fundamental ones. We may represent these different stages in production diagrammatically. Starting with the ores of copper and zinc, copper and spelter, though previous to the nineteenth century the ore of zinc called calamine or black jack was generally used, were made. The copper and calamine were mixed in proper proportions, and after being heated in the furnace for ten or twelve hours brass was produced. At this point the manufacturers had to deal with copper and brass in the form of ingots. Down to the end of the seventeenth century these ingots were bat1 Hunter, "History of Sheffield,” p. 156. 2 Patents, 1769, 901. 3 Annual Register, xviii, pp. 80-81. Patents, 1790, 1739. tered into plates with hammers moved by water wheels, but from about 1700 rolling mills were used for this purpose. If wire were desired, the plates were cut into strips, stretched on the rolling mill, and then drawn to the required thickness. Thus there were three main forms in which brass and copper were used, viz., ingots, sheets, and wire. The first was used chiefly by the brassfounders, patterns being prepared and impressed in sand, and the molten metal poured in, and so Zinc ore (calamine, black jack) Copper ore Prepared calamine Spelter Brass innumerable fittings required by the furniture maker or the plumber were made. In the case of sheet metal, until the eighteenth century the process employed was battery, such articles as pans and kettles being made with hammers. Later on rolling mills supplanted the battery mills, and this, it will be remembered, opened up the way for the stamped brassfoundry trade, which used sheet metal as its raw material and produced articles with the stamp and press machine. APPENDIX II OF YE VALUATION OF COPPER ORE,1 c. 1740 "First calcine two ounces of ye ore in a crucible, being first well pounded before it is weighed. Then stirring it in ye crucible with an iron rod in a red or rather black heat in ye furnace for some hours or till ye sulphur is evaporated, which you may know by ye smell of it being gone; taking care you don't give it much heat to run into a Regal (= Regulus). Then let your pot cool, and empty it upon paper and weigh out 2 ounces of Argol, 14 pennyweights of Saltpeter, and of Sal. Com. 10 pennyweights. If ye ore is stiff add some Salt of Tartar. "Then mix ye ore and fluxes together and put your crucible in ye furnace covered with a piece of crucible, charging it with Fresh Stone Coal, taking care no live black coal gets into ye crucible, and raising your heat in proportion to ye stiffness of your ore, and when you find it sufficiently fluxed and purged take out your pot and let it cool and break it. Then preserve ye Slags (or Scoria) and melt it down with some Salt of Tartar and preserve the metal found therein. Then to purify ye metal and make it a merchantable standard, of a small red grain (called Rose Copper), you cut it thro' with a cold chisel and break it and observe ye grain; if it beesit of a sufficient fineness, as it seldom is ye 1st melting. Then put it in a fresh crucible and give it a melting or a High Red Heat, then pour in your Salt of Tartar and Com. Sal. to run and purify it. Flow your pot, pour it into a thick iron ladle (well polished within and greasd to keep it from sticking). Then preserving ye slags melt them over again, adding salt of tartar, argol, and com. salt and weigh your purified produce. If it is Fine enough, or else melt again to purifie, and take 1 Common-Places, in relation to mines, minerals, metals, etc., by Louis Morris. Add. MS. 14,951, f. 16. |