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end, which is afterwards supplied by a separate piece or cap. The cores of many of these Birmingham brass-works are made to occupy so much of the pattern, that the brass is not thicker than a shilling.

Many of the brass-manufacturers who work on a large scale, employ a steam-engine to punch articles from sheet metal, from dies previously formed. By this operation almost all the common brass goods, (such as hand-plates to doors, roses to door and cabinet furniture, and many light goods) are now made. The punched goods are very cheap, but of very little strength or durability, as may be noticed in many of the brass articles employed in our domestic economy. Brass mouldings, plain or wrought, are generally cast solid, and in moderate lengths; a pattern in wood, clay, or wax, is required, and the only precautions previously to founding them are, that they be carefully indented in the sandtable. If the mouldings be large and much carved, a core may be used for these also, taking care to leave the metal sufficiently thick to allow of finishing up afterwards, without injuring the effect of the pattern.

All brass, as well as other foundings, require, when taken out of the sand, to be cleaned up and made complete; as they seldom come out perfect. This is done in brass-founding, by filing off the cores, and filling up the small holes with melted metal or solder. Some brass-works are cast to a rough pattern, for instance, all those which are cylindrical in shape; and such kind of goods are put into a lathe and turned, and smoothed up afterwards. Articles in brass which are sculptured, are generally left in a mat-state on their grounds, and the raised parts burnished up by hand; the mat-state refers to such parts only which are left without polish, or in a state in which the brass is found when it first comes out of the sand, with the addition of cleaning and perfecting only.

The burnishing consists in making the raised parts quite complete, and afterwards laying them down tight upon a bench, or in a vice, whichever is most convenient; and working up the face of the brass with a bent tool composed of a shaft of steel, about half an inch wide and eight or nine inches in length, fixed firmly in a handle of wood. The end of the tool is turned up about a quarter of an inch, and ground away on its inner edge. With this tool the workmen rub the part to be heightened, as it is termed. They have these heightening tools of various widths, some one-eighth of an inch wide only, and others as much as three-quarters of an inch. With such tools they operate upon all the various sized parts to be heightened; and, as the part is thus rubbed, the workman dips his tool in a lacker, which is standing near him in an earthenware dish. This lacker is commonly prepared from turmeric dissolved in spirits of wine, and which will be afterwards explained under the head of lackering.

Chasing, or enchasing as it is called, is also employed in brass works. It is a similar operation to heightening, except that it is employed in the more delicate works of sculpture to give them greater sharpness and effect. The French

excel in chasing, as their numerous small ornaments used as decorations to chimney-pieees time-pieces, vases, &c. &c., fully demonstrate; many of which are in brass as well as in or molu.

Brass castings which are plain are cleaned up for sale by being filed smooth or turned so by the turner, and afterwards polished by being rubbed with emery till the surface becomes regular and tolerably even, after which they are finished with tripoli. To keep brass works from tarnishing and getting black, by exposure to the air, the brass-workers have recourse to lacker ing. This consists in covering the brass, moderately heated over a stove containing an open charcoal fire, with a liquid, also moderately warm, composed of saffron and Spanish annotta, each two drams, put into a bottle with a pint of highly rectified spirits of wine, which when together should be placed in a moderate heat and often shaken from this a very strong tincture will be obtained, which must be afterwards strained through a coarse linen cloth to take out the dregs of the annotta and saffron; it is then to be returned to the bottle, and three ounces of seed-lac powdered must be added to it, and the whole again heated till the seed-lac be completely dissolved; after which it is fit for use, and will form a good and pale-colored lacker, which will prevent the brass from changing color by exposure to the air. It is laid on the brass by a camel's-hair pencil as thin as it can be spread, and requires nothing to be done to it after it is so spread but a moderate rubbing. If the brass be required to be of a redder color, increase the proportion of annotta in the lacker, and it will be accomplished. All the best kinds of brass-works are gilt to prevent their changing color, and this constitutes the desideratum in the works in or molu.

The more important part of casting in brass consists in founding statues, busts, basso-relievos, vases, &c. The Greeks and Romans practised it to an immense extent, as may be seen from the vast number of statues and other works which have come down to us of both these people. The Greeks also formed most of those instruments of brass, which we make of iron and steel. Thus Homer describes the arms offensive and defensive, in his poems, as brazen. He calls the Greeks by the general epithet of brass-coated, and seldom mentions steel. In Herculaneum, Pompeii, Stabea, &c., were found many arms and instruments formed of brass or bronze, while very few of iron were discovered. Those of brass were adapted to the purposes of agriculture, mechanics, mathematics, architecture, &c. In Pompeii was found a complete set of surgeons' instruments formed of bronze, which shows that a preference was given to that metal.

In the founding of statues, busts, &c., three things in particular require attention: namely, the mould, the wax, and shell or coat, the inner mould or core, so called from being in the middle or heart of the statue. In preparing the core, the moulder is required to give it the attitude and contour of the figure intended to be founded. The use of the core is to support the

wax and shell, to lesson the weight, and save the metal. The core is made and raised on an iron grate sufficiently strong to sustain it, and it is farther strengthened by bars or ribs of iron. The core is made of strong potter's-clay tempered with water, and mixed up with horse dung and hair, all kneaded and incorporated together; with this it is modelled and fashioned previously to the sculptor's laying over it the wax; some moulders use plaster of Paris and sifted brick-dust mixed together with water for their cores. The iron bars which support the core are so adjusted, that they can be taken from out of the figure after it is founded, and the holes are restored by solder, &c.; but it is necessary in full-sized figures to leave some of the iron bars affixed to the core to steady its projecting parts. After the core is finished and got tolerably firm and dry, the operation of laying on the waxen covering to represent the figure is performed, which must be all done, wrought and fashioned by the sculptor himself, and by him adjusted to the core. Some sculptors work the wax separately, and afterwards dispose and arrange it on the ribs of iron, filling up the void spaces in the middle afterwards with liquid plaster and brick-dust, by which plan the core is made as, or in proportion to, the sculptor's progress in working the wax-model. Care must be taken, however, in modelling the wax in both cases to make it of a uniform substance, in order to the metal being so in the work, of which the wax is its previous representative. When the waxen model is finished to the core, or adapted and filled afterwards, small tubes of wax are fixed perpendicularly to it from top to bottom, to serve not only as jets to convey the melted metal to all parts of the work, but as vent-holes to allow a passage to the air generated by the heated brass in flowing into the mould, and which, if not admitted readily to escape, would occasion so much disorder in, it as would much injure the beauty of the work. Sculptors adjust the weight of the metal required in this kind of founding by the wax taken up in the model. One pound of wax so employed will require ten pounds of metal to Occupy its space in the casting. The work having advanced in progress so far, will now require covering with a shell. This consists of a kind of coat or crust laid over the wax, which, being of a soft nature, easily takes and preserves the impression which it afterwards communicates to the metal, upon its occupying the place of the wax, which is between the shell and core. The shell is composed of clay and white crucible dust, well ground, screened, and mixed up with water to the consistence of paint, like which it is used. The moulder applies it by laying it over the wax with a camel's-hair or other soft pencil, which will require eight or nine times going over, allowing it time to dry between each successive coat. After this coating is firm upon the wax, and which is used only to protect it from those which are to follow, the econd part, or coating, is made up of common earth, mixed with horse-dung: this is spread all over the model, and in such thickness as to withstand, in some measure, the weight of the

intended metal. To this coating or impression is added a third, composed almost wholly of dung, with a proportion of earth sufficient only to render it a little more tough and firm when used. When this is tolerably dry, the shell is finished by laying on several more coats or impressions of the same composition, made strong and stiff by successive workings with the hand. When this is finished, and is deemed adequate to support the heated metal, it is farther secured and strengthened by several bands or hoops of iron, bound round it at about six inches from each other, and fastened at bottom to the grate on which the statue stands. Above the head of the statue is made an iron circle for the purpose also of confining the shell and statue, to this circle the hoops are fastened at top. It may be considered when the moulding has arrived at this state, to be in a condition to receive the melted metal; but it is not so exactly, as will soon appear. The mould, as has been before observed, is made upon an iron grate: under this grate is a furnace and flue, in which at this period of the work a moderate fire is to be made, and the aperture of communication therewith stopped up so as to keep in the heat. As the heat increases, and begins to operate on the mould, preparation must be made to allow of the wax running freely from out of the shell: for this purpose, pipes are contrived at the base of the mould, so that it may run gently off and through these pipes. As soon as it is all run off, the pipes are nicely stopped up with earth to prevent the air entering them, &c. When this is done, the shell is surrounded by any matter that has non-conducting properties, for instance, pieces of brick put round and piled up of good thickness, secured by earth, will answer the end; and the whole should be finally coated outside with loam as a farther protection to keep in the heat.

After the shell is adequately surrounded with materials to keep off the effect of the air, the fire in the furnace is augmented, till such time as both the matter surrounding the shell and it also become red-hot, and which in ordinary circumstances will take place in twenty-four hours' time; the fire is then extinguished, and the whole allowed to cool: after which, the matter which has been packed round the shell is taken away, and its place occupied with earth moistened and closely pressed to the mould in order to make it more firm and steady. It will, when having advanced so far, be in a state to receive the melted metal; to prepare which for the casting, a furnace is made a few feet above the one employed to heat the mould: it is formed like an oven, having three apertures, one of which is for a vent, the other to admit the fuel, and the last to let the melted metal flow through and out of the furnace. This last aperture should be kept very close whilst the metal is fusing, when it has arrived at that state which is deemed proper for running it into the shell, and which is known by the quick separation and escape of the zinc of the brass. A little tube is laid to convey it into an earthenware basin, which is fixed over the top of the mould. Into this basin all the large branches from the jets

enter, and from which is conveyed the metal into all the parts of the mould. The jets are all stopped up with a kind of plugs, which are kept close till the basin which is to supply the metal be full. When the furnace is first opened for this purpose, the melted brass gushes forward like a torrent of fire, and is prevented from entering any of the jets by the plugs, till the basin is sufficiently full to be ready to begin with the mould, and which is esteemed so when the brass it contains is adequate to the supply of all the jets at once, upon which occasion the plugs from all of them are withdrawn. The plugs consist of a long iron rod, with a head at one end capable of filling the whole diameter of each tube. The hole in the furnace in which the melted metal is contained, is opened with a long piece of iron, fitted on the end of a pole to allow of the furnace-man keeping at a distance from it, as many accidents occur by the red-hot metal coming in contact with the air, particularly if it be damp, in which case the most violent explosions take place. The basin is filled almost in an instant after the furnace-plug is withdrawn, and the metal is then let into the several jets communicating with the model, which when they have emptied themselves into the shell or mould, the founding is finished, in as far as the casting is concerned. The rest of the work is completed by the sculptor, who takes the new brass figure from out of the mould and earth in which it was encompassed, saws off the jets, and repairs and restores the parts where required. His tools for this purpose consist of chisels of various sizes, gravers, puncheons, files, &c.

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In casting colossal statues a somewhat different mode is pursued than the one already described this arises wholly from the size, it being found difficult to remove the moulds of such works; they are therefore worked and prepared upon the spot where they are to be cast. There are two ways of performing this. By the first plan a square hole is dug into the earth some what larger than would be required for the mould, and its sides are hemmed up with brickwork at its bottom is formed a hole below the bottom of the one already prepared, as a furnace, and which must be built up with brick-work, having an aperture made outwards into another pit prepared near it, from which the fuel is put into the furnace. The top of the furnace in the first hole is covered by a grating of iron, and on this is moulded and placed the case of the statue to be cast, and also its waxen coating; in doing which the same process is observed by the sculptor as that already described. Near the edge of the large pit, in which the model is placed, is erected the furnace to melt the metal, and which is similar to the one already described for common figure-casting, except being of larger dimensions; it has like that three apertures, one for putting in the wood, another for vent, and a third to run the metal out at. By the second plan of founding colossal figures, it is thought sufficient to work the mould above ground, adopting the same mode with respect to a furnace and grate underneath it. For, whether under ground or above it, to keep in the heat VOL. IX.

when drying the core and melting the wax, is that which is more particularly sought for, to do which, in the most effectual way, four walls of brick-work are built up round the model, in the middle of which is fixed the grate and furnace; and on one side above is formed the mass of building intended for the furnace, which is to be appropriated to the melting of the metal. When the whole is finished and ready, a fire is made in the fire-place under the core of the model, and kept up so as to produce a moderate heat to dry the core, and also to melt away the wax from off it, which runs down by tubes as has been before remarked upon, and indeed no difference whatever takes place in such founding, except every thing being on a larger scale. When the wax is run off, and the fire extinguished in the furnace, bricks are filled in at random, either into the hole, if founding under ground, or into the area between the walls if above ground; after this is done the fire in the furnace is again lighted, and blown up and augmented, till such time as both the core and bricks are of a red-heat; when the fire is again extinguished, and the whole is left to cool; and when cooled the bricks are again removed, and all is cleared away, and the space again occupied by moistened earth to secure and steady the model. Nothing now remains but running in the metal, which is performed as has been before described for smaller foundings of statues.

All the principal cities of ancient Greece and Rome, boasted of their wealth by enumerating their statues of brass. Athens, Delphi, and Rhodes, are each reported to have had in and about their temples 3000 brass statues. And Marcus Scaurus, though an edile only, adorned the circus at Rome with upwards of that number of statues of brass, during the time of the celebrating of the Circensian shows. It afterwards, in consequence of this taste continuing to prevail at Rome, of forming and collecting works in brass, used to be a proverb among the visitors of that celebrated city, that in Rome the people of brass were not less numerous than the Roman people.'

BRONZE, by the Italians called Bronzo, was well known to the ancients. Egyptians, Greeks, and Romans all made use of it, and that in most cases to their important works as connected with sculpture and the ornamental parts of architecture. Bronze was selected by these people as bearing a finer edge, and not so likely as either of its component parts to oxydate by exposure to the air: hence they made statues of it to adorn the approaches to their cities and public edifices, affixed it in beautiful and highly relieved ornaments to the friezes of their temples, cast it in basso-relievos to represent the paraphernalia of their games and festivals, which were retained in compartments about their works dedicated to their gods; and, finally, wrought it into baths, tripods, vases, lamps, and other purposes of utility and ornament; specimens of many of which have by its indestructibility come down to us, as may be seen exhibited in the numerous public galleries on the continent, at Rome. Naples, Florence, and Paris, with some in our own Museum. 2 K

The Egyptian bronze consisted, according to Basari, of two-thirds brass, and one-third copper. Pliny says, 'the Grecian bronze was formed by adding one-tenth lead, and onetwentieth silver, to the two-thirds brass and the one-third copper of the Egyptian bronze,' and this was the proportion afterwards made use of by the Roman statuaries. The Greek bronzes very obviously appear to possess a difference of composition to any that have been founded among the moderns. The famous Venetian horses (four in number), said to have been the work of Lysippus, exhibit at once, to bronzists, that the ancient metal of that name was, in its composition, very different from that which is now made and called after that designation :-the modern bronze is commonly made of two-thirds copper, fused with one-third of brass; and very lately, from the great demand for all kinds of ornaments in this metal, in forming the decorative parts to pur apartments, and supports to our articles of furniture, lead, with zinc in small proportions, have been added to the copper and brass. These rariations have been one cause of the greater brilliancy and compactness to be observed in modern castings of this metal, in comparison of those founded a few years since. So common is bronze-work become at this time, that every petty brass-worker pretends to be an adept in founding of this metal; however, nothing is to be feared in the attempt, as the efforts of such bronzists will not carry them beyond the work of the furnace.

The alloying of the several metals to form bronze is found to promote in it a readier fusibility than is possessed by either of its component parts in their pure metallic state; and this is a property very much to its advantage in the castings of large works. Modern works in bronze become numerous in proportion to the advancement in the arts. Bronze-casting is employed in forming equestrian statues, colossal and other figures in alto-relievo, to set off and adorn public places. It is competent, when in the hand of an artist, of giving a zest to architecture; inasmuch as by its tint, as well as by the great variety of the forms it is susceptible of being made into, it is able to add richness by its opposition, and at the same time it finishes the forms of those parts of architecture requiring it. See BRONZE. In that article we have noticed Macqueir's mode of casting large works.

Bronze-casting is also performed in the following manner, viz. 1. The figure or pattern to be cast must have a mould, and this is prepared and laid on a plaster cast, previously wrought and finished by the sculptor. The mould is made of plaster of Paris, rendered moist by being mixed up with water; to this preparation is added brick-dust, in the proportion of one-third of the former to twothirds of the latter. This is carefully laid on the mould, with strength in proportion to the weight of metal intended to be used in the founding. In its joints small channels should be cut tending upwards, and from different parts of the internal hollow, to allow of vent for the air to escape through, as the heated metal runs in upon the mould. A thin layer of clay should be spread

over the inside of it, and of the thickness which it is intended the bronze should be. Within-side the clay, a filling up of plaster and brick-dust, in the proportions as before described, will be required to compose the core: but, if the work to be cast be large, before the plaster and brickdust are poured into the mould to form the core, a skeleton composed of iron bars, as a support for the figure, should be prepared and fixed; after which the filling up of the core may be proceeded in. When this is done, the mould must be opened again, and the layer of clay taken out of it, and the core thoroughly dried, and even burned with a charcoal fire, or with straw; for, if the least damp remain, the cast will be blown to pieces when the hot metal comes in contact with it, in running it into the mould, and the workmen employed about the work be maimed or killed by the dispersion of the heated bronze. After the core, &c., has been properly dried, and is deemed ready for the work, it should be laid in the mould, and supported in its place by short rods of bronze, which should run through the mouid into the core. All being so far advanced, the mould should be clad and bound round with iron, of strength proportionate to the size of the work to be cast; after which, the mould should be laid in a situation for running in the metal, and must be supported for the purpose by bricks, &c. Great care should be taken that every part be perfectly dried, before any metal be run into the mould; or, as has been before observed, the most fatal consequences will arise to those who may be about the work. A channel must be made from the furnace in which the melted metal is, in order to its running to the principal jet of the mould, and with a descent, to promote its flowing rapidly. The jets, furnace, &c. &c., are all contrived, as has been before described, for casting figures in brass. In Vesaris's Lives is a chapter on brass-founding; and there are also some very useful observations in the Life of Beivenuto Cellin; vide Pliny's Natural History.

The smaller works in bronze are founded by previously being modelled in wax, to which a coating of clay is adapted and dried.

Bronze works are cleaned up and repaired after being founded, in a similar manner to what figures in brass are, and with the same kind of tools; but this last touch of perfecting what may have been left imperfect by the mould, should invariably be done by the statuary or modeller himself; as no one is so competent to keep up the spirit of the original work, as he who invented it, and gave effect to his invention, by making the model.

The principal works executed in London in bronze, claiming particular notice, are, the equestrian statue at Charing Cross, of Charles I.; the colossal statue of his late majesty, in the square of Somerset Place, by the late Mr. Bacon; the statue of Francis, duke of Bedford, on the south side of Russell Square: the equestrian statue of William III., in the centre of St. James's Square, the work of Mr. J. Bacon, jun.; and the Achilles,' in commemoration of Lord Wellington's victories, in Hyde Park. There

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are also many bronzes of great merit in the proThe manner of casting BELLS is similar to that of statues, except that the metal is different, there being in bell-metal about one fifth of tin, whereas there is no tin in the brass of statues. The dimensions of the core and wax in modelling a bell, if it be to be one of a ring of several, must be formed on a kind of scale or diapason, which will give the height, aperture, and thickness of the shell necessary to the several tones required. The exterior of the bell is formed into rings fashioned into mouldings, and sometimes inscriptions, mottos, and figures are also added to adorn its exterior; all these are previously modelled and afterwards moulded in wax upon the core. The clapper or tongue is not properly a part of the bell, and is furnished by other hands; with us it is usually of iron, and is suspended in the middle of the bell. The Chinese make it of wood, leaving a hole under the cannon of the bell to increase its sound. Our proportions of bells consist in making the diameter fifteen times as thick as the brim, and its length twelve times. The bell itself consists of its sounding bow, which is terminated by an inferior circle, which diminishes thinner and thinner as it approaches to the brim or that part on which the clapper strikes, and which is required to be left rather thicker than the rest both above and below; also the outward sinking or properly the waist of the bell, or the point under which it grows wider to the brim; and the upper vase, or top or dome of the bell, or that part which is above the waist. The pallet is the inside of the vase or dome to which the clapper is suspended. The vent and hollowed branches of metal which unite with the cannon to receive the iron keys by which the bell is hung to its beam of support, where it must be exactly counterpoised. The height of a bell is in proportion to its diameter as twelve is to fifteen, or in the proportion of the fundamental sound to its third major, from which it follows that the sound of a bell is principally composed of the sound of its extremity or brim as a fundamental of the sound of the crown, and which is an octave to it, and that of the height, which is a third.

ments or inscriptions to be cast upon the bell are
put. A hole is now dug of an adequate depth
to contain the mould of the bell, together with
the case of it, or cannon, under ground, and
about six inches below the level of the ground of
the foundry. It must be wide enough to allow
of a free passage between the mould and walls,
or between one mould and another when several
bells are to be cast.
At the centre of the hole a
stake is erected, which is fixed firmly in the
ground; this supports an iron peg, on which the
pivot of the second branch of the compasses of
construction turns: these compasses are the chief
instruments for making the mould, and consist
of two legs joined to a third at its apex. The
stake is surrounded by solid brick-work, of about
six inches in height and of the diameter of the
bell; this is called the mill-stone. The parts
of the mould consist of the core, the model of
the bell, and the shell.

When the outer surface of the core is formed,
it is raised up with bricks, which are laid in
courses of equal height upon a layer of earth;
as each brick is laid the work is brought near to
the branch of the compasses on which the curve
of the core is shaped, so as that there may re-
main between it and the curve the distance of a
line, to be afterwards filled up with layers of ce-
ment. The building of the core is continued to
the top, leaving only an opening for the coals to
be put in to bake the core. This work is covered
with a layer of cement made of earth and horse-
dung, and on which is moved the compass of
construction, to make of an even smoothness
every where. Having fasted me frst layer in
this way, the fire is put into the core by fling t
half with crals thug an opening kept shue
during the baxing, and with a case if y
which has been secantery saved The ira ire
consumes the make, and is et ne se a
half and sometimes a winie tag: he inst aver
having became nergy ty, i suvered with
a second, as a turd and burn, an yang er-
rounded with a man and as the compassed
and as many tret vim moteris im

der The same eng time inishes be pass in tan ʼn ges with the nece of mating av te futes if he inst To mould a bell for casting, the following pre- tone te na ter parations must be made. Earth must be col pan another sure if he not Te lected, and that which is most cohesive is the es va mean ý best, and it must be well ground and sufted aced with be and in the swee Brick or stone must be obtained for the mines her ai com rete i im with which it must be stained. Horse-dung Tus the work

hair, and hemp, must be mixed with the earl
to render the composition for moulding mom
firm and binding. The wax to mould the
scriptions, coats of arms, and other
about the outer surface of the bell:

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must be mixed with the wax in equal amon

tions, to make it mould more fre

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upon the model or outer mould, pre

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any of the ornaments being app & L
scaffold is raised upon tressels round he
upon which is placed the earth gre

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with water, to make it mix better with the m and, last of all, shelves are 12x a which the models, &c., of the dina m

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