The metal most suitable for artistic work is an alloy of copper and tin, either with or without the addition of zinc, lead, or both. The mixture used by the Kellers was, copper 91.4; zinc 5.53; tin 1 • 7; lead 1 • 37. Copper 87. 8; zinc 6.52; tin 5.1; lead 058; gives also a very good metal. Copper 93, tin 7, gives an excellent bronze. An equal quantity of yellow brass mixed with this gives an excellent and easy-flowing metal. Bronze is usually considered to be improved in colour by using zinc, and lead is supposed to aid it greatly in flowing. Tin gives great hardness, and when the amount of tin used is over 20 per cent, the metal becomes useless for artistic purposes. A bronze composed pf copper and 3-4 per cent, of rarher sluggish, find requires more nice management as to the degree of heat

Metal Work Brozes Part 7 500137Metal Work Brozes Part 7 500138

If the crucibles used are those known as the Salamander brand, there are no precautious to be observed. The crucible stand is placed on the bars at the bottom of the empty furnace. The height of this stand should be such as to bring the top of the crucible 2 in. below the throat of the furnace. The stand should have a thin layer of ashes on it, to prevent the crucible sticking to it. Then put in as much metal as the crucible will contain, and cover it over with a proper cover: throw 2 or3 shovelfulls of live coke into the furnace, and fill up all round your crucible with good clear broken coke up to the level of the crucible top. Place some large pieces of coke on top, taking care that they do not get in the throat of the furnace, and so choke the draught. Put on the cover of your furnace and draw out the damper, and fire as hard as you can until you find that the metal has run; then add more and more by degrees until you have a full charge. Some keep a thick layer of charcoal dust on top of the metal, others do not take any precaution to prevent the formation of dross. Most persons, however, add a little borax, which powerfully cleanses the metal.

It must be well skimmed off before pouring.

Status foundry.

Status foundry.

When the metal is ready to be withdrawn from the furnace, the coke must be cleared away from the pot, so as to make room for the crucible tongs. These are placed over the pot, and kept closed by a ring. The pot is then lifted vertically by one or by two men, and if it is a small one it is poured at once out of the tongs, but if it is a large one it is placed ,in a receptacle called a cradle, which is carried' by two or more men. Sometimes it is poured into a hand ladle, or shank, and thence into the mould. This is not, however, usually done unless the contents of several crucibles is required, and then it is better to form a large basin, or core, at the top of the mould, the openings of the jets being closed with plugs. All the crucibles should be poured into this basin before drawing the plug; this ensures a clean casting, as all impurities float on the surface, and are not carried into the mould, When this basin is not used, it is of the utmost importance that the bronze should be thoroughly, skimmed. If the metal runs down quietly, and rises up in the vents till it reaches the surface, it is a sure sign that the mould has filled properly.

If, on the other hand, it makes much noise, and, worst of all, if it spurts and splutters in going down, and does not rise up again in the vents, it is certain that the casting is a failure.

The moulds for small - indeed for all - work should be broken down as soon as practicable after the metal has set, but great care must be used not to expose the surface of the casting too soon, for while it is red hot bronze is extremely fragile and liable to injury. The statue, on being freed from its mould, will be found with its system of jets and vents perfect as they were made in wax. These are then cut off with a saw as near as convenient to the surface of the statue. The figure is then well brushed with wire brushes, to remove all the particles of the mould; it is then placed in a bath of very dilute acid to pickle, as it is called. This cleans the surface of the metal very completely, and the artist can then repair any little defect that remains, as, for instance, the places where the jets have been and the like, after which it is usual to give the work its patina or colour, which is produced by the action of various salts and acids on the surface of the bronze. A great variety of tints are obtainable, and in the selection of these every artist will, of course, exercise his own taste and judgment.

Although there are, both in England and abroad, excellent statue founders, whose work leaves nothing to be desired as far as the ordinary run of bronze work is concerned, and who are even able to go considerably beyond the average requirements of commercial sculpture, yet it is a matter of deep regret' that autograph work in bronze is almost non-existent in England at the present time. Sculptors used, even in this country, to be their own bronze founders, and that at no yery distant date,

If artists could be persuaded to become once more their own founders, as far, at least, as small works are concerned, I do not think that it would be a matter for regret even to the manufacturers of cabinet bronzes. These would still command a large sale, as the autograph works produced by artists would of necessity be higher in price and few in number. It may be objected that bronze casting is not an artistic but a mechanical employment. Against this view of the case I must earnestly protest, as my own experience is that bronze casting requires quite as much artistic skill as marble carving, and that neither the one nor the other should be in other hands than the artist's own. (G. Simonds.).

It is necessary, in the wax process, that the mould shall be hot, but it is not made hot on purpose; the bronze is poured in as soon as the mould is cool enough. In small castings, the hotter it is the better, so that it is not red-hot; in large castings it should be pretty cool, because the body of metal being so large, it heats the mould so much, that if it were too hot at first, it would produce sandburn on the surface. The joining of the pieces is done by the box-joints already described; a small rim of metal is left standing at the edge of each joint, and when the two are fitted together, these little rims are screwed or riveted together, and then the metal is worked down with punches. Sometimes they are burned together. In order that the colour may be uniform, it is necessary, that, when casting a subject in many parts, the whole of the metal should be mixed at once, whether it be cast all at once or not, so that there may be no mistake about getting the same alloy each time.