Before concluding the remarks on raised works, it may be desirable to revert to some of the principal and distinguishing features of the tools employed in these arts. As a general rule, it will be observed that all these manifold shapes are the more quickly obtained, the more nearly the various tools assimilate to the works to be wrought. For instance, the several dies and swage tools quickly and accurately produce mouldings, of the specific forms of the several pairs of dies; but it is utterly impossible to extend this method to all cases, and the progressive changes required, from the flat disk, the cylinder or cone, as the case may be, to the finished object; and therefore certain ordinary forms of tools can alone be employed, and they are continually changed as the work proceeds.

For hollow works with contracted mouths, the inner tools are required gradually to decrease in bulk and to increase in length, in order to enter the cavities; but they can be rarely the exact counterparts of the transient forms of the works, nor is it always desirable they should be so. The tools are often required to be bent at the end, to extend within a shoulder or gorge; the small stake in the tool, fig. 220, p. 386, is an example of this; the dotted line represents the work, such as the perforated cover of a cylinder, or the top of a teakettle: the strong wrought-iron arm or horse, fig. 220, carries the small steel tools, and which latter, may be also fixed by their shanks either in the bench or vice, according to circumstances.

There are many curious circumstances respecting the modification of the materials for, as well as the forms of, the hammers and anvils, if the use of these terras may be extended to the various contrivances, by the action and re-action of which thin metal works are produced; and the concluding examples are advanced to bring some of these peculiarities of method into notice.

The plated metals have so thin a coating of silver, that they require more expert hammering than similar works in solid silver, otherwise the removal of the bruises left by the hammer, by scraping and polishing, might wear through the silver and show the. copper beneath. The bruises are therefore driven to the copper side, by hammering upon the silver or the face, with a very smooth planishing hammer, and covering the anvil or bottom tool with cloth. On account of the elasticity thus given, the blows become so far hollow that all the little bruises descend to the copper side, or that which is exposed to the cloth, and the face becomes perfectly smooth.

When the inside of a vessel is required to be smooth, it is the hammer that is covered with cloth, stretched over it by an iron ring and the polished stake or head within the vessel is left uncovered; and in those cases in which the work is required to be good on both sides, the faces both of the hammer and anvil are each muffled; this gives them some of the elasticity of wooden tools, but with superior definition of figure.

Plated works are generally furnished with an additional thickness of silver at the part to be engraved with a crest or cypher, in order that the lines may not penetrate to the copper, (see page 282;) should it, however, be requisite to remove the engraved lines for the substitution of others, the following mode is resorted to.

The object is laid upon the anvil over a piece of sheet lead and it is struck with a bare hammer upon the engraved lines, these latter are therefore hollow as regards the face of the hammer; in consequence of which, the reaction of the lead causes it to rise in ridges corresponding with the engraved lines, and to drive the thin plated metal before it. The device is thus in great measure obliterated from the silver face and thrown to the copper side, so as to leave much less to be polished out; this ingenious method is appropriately called reversing.

In making vases, such as figs. 209 and 211, page 383, the metal is first driven into concave wooden blocks with a wooden mallet, as in fig. 273, page 402, in order to gather up the metal into the fluted concave 275, page 403, but without making any sensible alteration in its thickness. In the next stage of the work, metal tools are alone employed, whether the object be made by raising-in with hollow blows, or by setting-out with solid blows as adverted to; and the sizes and curvatures of the tools require to be accommodated to the changes of the work.

Supposing the vases to have either concave or convex flutes, escutcheons, or similar ornamental details, they are now sketched with the compasses upon the plain surface of the vase; and if from the shape of the works swage tools similar to fig. 229, p. 3S6, cannot be employed for raising the projecting parts, they are snarled-up, by the method represented overleaf in fig. 284.

Thus at v, are the jaws of the tail vice, in which the snarling-iron s, is securely fixed; the extremity b, which is turned up must be sufficiently long to reach any part of the interior of the vessel, but yet small enough to enter its mouth. The work is held firmly in the two hands, with the part to be raised or set-out exactly over the end b; and when the snarling-iron is struck with a hammer at h, the reaction gives a blow within the vessel, which throws the metal out in the form of the end of the tool, wheather angular, cylindrical, or globular: except in small works, two indi-viduals are required, one to hold and the other to strike.

Section III Peculiarities In The Tools And Methods 100133

Figure 285 shows the last stage of the work prior to polishing; thus in finishing the flutes and other ornaments after they are snarled-up, the object is filled with a incited composition of pitch and brick-dust, sometimes the pitch is used alone, orcommon resin is added; the ornaments arc nowcorrected with punches or chasing tools of the counterpart forms of the several parts; some portions of the metal are thus driven inwards, whilst those around rise up from the displacement and re-action of the pitch. To avoid injuring the lower surface of the work it is supported upon a sand bag b, like those used by engravers, and the perpendicular lines p, denote the usual position of the chasing tool.

Works in copper and brass are sometimes filled with lead at the time of their being chased, but the silversmiths and goldsmiths are studious to avoid the use of this metal, as if it gets into the fire along with their works, it is very destructive to them.

Pitch and mixtures of similar kind, are constantly used in the art of chasing in its more common acceptation; from its adhesive and yielding nature it is a most appropriate support, as it leaves both hands at liberty, the left to hold the punch, the right for the small hammer used in striking it.

The pitch-block, fig. 280, is employed to afford the utmost choice of position, for works from the smallest size to those of six or eight inches long. The lower part is exactly hemispherical, and it is placed upon a stout metal ring or collar of corresponding shape, covered with leather. The mass of metal makes a firm solid bed to sustain the blows, and the ball and socket contact, allows the work to assume every obliquity, and to be twisted round to place any part towards the artist.

Large flat works in high relief are frequently sketched out and commenced from the reverse face, the prominent parts of the subject being sunk into the pitch, which after a short time must be melted away to allow the metal to be annealed; and this is frequently required when the works are much raised. In the concluding steps the artist works from the face side.

Many of the chased works are cast in sand moulds from metal models, which have been previously chased nearly to the required forms; the castings are first pickled to remove the sand coat, and in such cases, chisel and gravers are somewhat used in removing the useless and undercut parts.*

The art of chasing may be considered as the sequel to that of forging (that is, setting aside the employment of the red-heat), but the various hammers and swage tools now dwindle into the most diminutive sizes, and are required of as many shapes as may nearly correspond with every minute detail of the most complex works. Some of them are grooved and checkered at the ends, and others are polished as carefully as the planishing hammers, that they may impart their own degree of perfection and finish to the works; in a similar manner that the polish and excellence of coins and medals are entirely due to that of the dies from which they are struck, the chasing process being, as it were, a minute subdivision of the action of the die itself.