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end, which is afterwards supplied by a separate excel in chasing, as their numerous small ornapiece or cap. The cores of many of these Bir- ments used as decorations to chimney-plete's mingham brass-works are made to occupy so time-pieces, vases, &c. &c., fully demonstrate; much of the pattern, that the brass is not thicker many of which are in brass as well as in or than a shilling.
molu. Many of the brass-manufacturers who work Brass castings which are plain are cleaned up on a large scale, employ a steam-engine to punch for sale by being filed smooth or turned so by articles from sheet metal, from dies previously the turner, and afterwards polished by being fornied. By this operation almost all the com- rubbed with emery till the surface becom mon brass goods, (such as hand-plates to doors, regular and tolerably even, after which they are roses to door and cabinet furniture, and many finished with tripoli. To keep brass works from light goods) are now made. The punched goods tarnishing and gettive black, by exposure to the are very cheap, but of very little strength or du- air, the brass-workers have recourse to lacker rability, as may be noticed in many of the brassing. This consists in covering the brass, moderarticles employed in our domestic economy. ately heated over a stove containing an open Brass mouldings, plain or wrought, are gene- charcoal fire, with a liquid, also moderately rally cast solid, and in moderate lengths; a pat- warm, composed of saffron and Spanish annotta, tern in wood, clay, or wax, is required, and the each iwo drams, put into a bottle with a pint of only precautions previously to founding them highly rectified spirits of wine, which when are, that they be carefully indented in the sand- together should be placed in a moderate heat table. If the mouldings be large and much and often shaken · froin this a very strong tinccarved, a core may be used for these also, taking ture will be obtained, which must be afterwards care to leave the metal sufficiently thick to allow strained through a coarse linen cloth to take out of finishing up afterwards, without injuring the the dregs of the annotta and saffron; it is then effect of the pattern.
to be returned to the bottle, and three ounces of All brass, as well as other foundings, require, seed-lac powdered must be added to it, and the when taken out of the sand, to be cleaner up whole again heated till the seed-lac be comand made complete; as they seldom come sut pletely dissolved; after which it is fit for use, perfect. This is done in brass-founding, by file and will form a good and pale-colored lacker, in: off the cores, and filling up the small holes which will prevent the brass from changing with melted metal or solder. Some brass-works color by exposure to the air. It is laid on the are cast to a rough pattern, for instance, all those brass by a camel's-hair pencil as thin as it can which are cylindrical in shape; and such kind of be spread, and requires nothing to be done to it goods are put into a lathe and turned, and after it is so spread but a moderate rubbing. If smoothed up afterwards. Articles in brass which the brass be required to be of a redder color, are sculptured, are generally left in a mat-state increase the proportion of annotta in the lacker, on their grounds, and the raised parts burnished and it will be accomplished. All the best kinds up by hand; the mat-state refers to such parts of brass-works are gilt to prevent their changing only which are left without polish, or in a state color, and this constitutes the desideratum in in which the brass is found when it first comes the works in or molu. out of the sand, with the addition of cleaning The more important part of casting in brass and perfecting only.
consists in founding statues, busts, basso-relievos, The burnishing consists in making the raised vases, &c. The Greeks and Romans practised parts quite complete, and afterwards laying them it to an immense extent, as may be seen from down tight upon a bench, or in a vice, whichever the vast number of statues and other works is most convenient; and working up the face of which have come down to us of both these the brass with a bent tool composed of a shaft people. The Greeks also formed most of those of steel, about half an inch wide and eight or instruments of brass, which we make of iron nine inches in length, fixed firmly in a handle and steel. Thus Homer describes the arms of wood. The end of the tool is turned up offensive and defensive, in his poems, as brazen. about a quarter of an inch, and ground away on He calls the Greeks by the general epithet of its inner edge. With this tool the work men rub brass-coated, and seldom mentions steel. In the part to be heightened, as it is termed. They Herculaneum, Pompeii, Stabea, &c., were found have these heightening tools of various widths, many arms and instruments formed of brass or some one-eighth of an inch wide only, and others bronze, while very few of iron were discovered. as much as three-quarters of an inch. With Those of brass were adapted to the purposes of such tools they operate upon all the various sized agriculture, mechanics, mathematics, architecparts to be heightened; and, as the part is thus ture, &c. In Pompeii was found a complete rubhed, the workman dips his tool in a lacker, set of surgeons' instruments formed of bronze, which is standing near him in an earthenware which shows that a preference was given to that dish. This lacker is commonly prepared from metal. turmeric dissolved in spirits of wine, and which In the founding of statues, busts, &c., three will he afterwards explained under the head of things in particular require attention : namely, lackering.
the mould, the wax, and shell or coat, the inner Chasing, or enchasing as it is called, is also mould or core, so called from being in the eniployed in brass works. It is a similar opera- middle or heart of the statue. In preparing tion to heightening, except that it is employed the core, the moulder is required to give it the in the more delicate works of sculpture to give attitude and contour of the figure intended to be them greater sharpness and effect. The French founded. The use of the core is to support the wax and shell, to lessen the weight, and save intended metal. To this coating or impression the metal. The core is made and raised on an is added a third, composed almost wholly of iron grate sufficiently strong to sustain it, and it dung, with a proportion of earth sufficient only is farther strengthened by bars or ribs of iron. to render it a little more tough and firm when The core is made of strong potter's-clay tem- used. When this is tolerably dry, the shell is pered with water, and mixed up with horse- finished by laying on several more coats or imdung and hair, all kneaded and incorporated pressions of the same composition, made strong together; with this it is modelled and fashioned and stiff by successive workings with the hand. previously to the sculptor's laying over it the When this is finished, and is deemed adequate wax; some moulders use plaster of Paris and to support the heated metal, it is farther secured sifted brick-dust mixed together with water for and strengthened by several bands or hoops of their cores.
The iron bars which support the iron, bound round it at about six inches from core are so adjusted, that they can be taken from each other, and fastened at bottom to the grate out of the figure after it is founded, and the on which the statue stands. Above the head of holes are restored by solder, &c.; but it is ne- the statue is made an iron circle for the purpose cessary in full-sized figures to leave some of the also of confining the shell and statue, to this iron bars affixed to the core to steady its project- circle the hoops are fastened at top. It may be ing parts. After the core is finished and got considered when the moulding has arrived at tolerably firm and dry, the operation of laying this state, to be in a condition to receive the on the waxen covering to represent the figure is melted metal ; but it is not so exactly, as will performed, which must be all done, wrought soon appear. The mould, as has been before and fashioned by the sculptor himself, and hy observed, is made upon an iron grate : under him adjusted to the core. Some sculptors work this grate is a furnace and flue, in which at this the wax separately, and afterwards dispose and period of the work a moderate fire is to be made, arrange it on the ribs of iron, filling up the and the aperture of communication there with void spaces in the middle afterwards with liquid stopped up so as to keep in the heat. As the plaster and brick-dust, by which plan the core heat increases, and begins to operate on the is made as, or in proportion to, the sculptor's mould, preparation must be made to allow of progress in working the wax-model. Care the wax running freely from out of the shell: must be taken, however, in modelling the wax for this purpose, pipes are contrived at the base in both cases to make it of a uniform substance, of the mould, so that it may run gently off and in order to the metal being so in the work, of through these pipes. As soon as it is all run off, which the wax is its previous representative. the pipes are nicely stopped up with earth to When the waxen model is finished to the core, prevent the air entering them, &c. When this or adapted and filled afterwards, small tubes of is done, the shell is surrounded by any matter wax are fixed perpendicularly to it from top to that has non-conducting properties, for instance, bottom, to serve not only as jets to convey the pieces of brick put round and piled up of good melted metal to all parts of the work, but as thickness, secured by earth, will answer the vent-holes to allow a passage to the air gener- end; and the whole should be finally coated ated by the heated brass in towing into the outside with loam as a farther protection to keep mould, and which, if not admitted readily to in the heat. escape, would occasion so much disorder in it After the shell is adequately surrounded with as would much injure the beauty of the work. materials to keep off the effect of the air, the Sculptors adjust the weight of the metal re- fire in the furnace is augmented, till such time quired in this kind of founding by the wax as both the matter surrounding the shell and it taken up in the model. One pound of wax so also become red-hot, and which in ordinary ciremployed will require ten pounds of metal to cumstances will take place in twenty-four hours' occupy its space in the casting. The work time; the fire is then extinguished, and the having advanced in progress so far, will now whole allowed to cool: after which, the matter require covering with a shell. This consists of which has been packed round the shell is taken a kind of coat or crust laid over the wax, which, away, and its place occupied with earth moistbeing of a soft nature, easily takes and pre- ened and closely pressed to the mould in order serves the impression which it afterwards com- to make it more firm and steady. It will, when municates to the metal, upon its occupying the having advanced so far, be in a stale to receive place of the wax, which is between the shell the melted metal; to prepare which for the and core. The shell is composed of clay and casting, a furnace is made a few feet above the white crucible dust, well ground, screened, and one employed to heat the mould: it is formed mixed up with water to the consistence of paint, like an oven, having three apertures, one of like which it is used. The moulder applies it which is for a vent, the other to admit the fuel, by laying it over the wax with a camel's-hair or and the last to let the melted metal flow through other soft pencil, which will require eight or and out of the furnace. This last aperture nine times going over, allowing it time to dry should be kept very close whilst the metal is between each successive coat. After this coating fusing, when it has arrived at that state which is is firm upon the wax, and which is used only to deemed proper for running it into the shell, and protect it from those which are to follow, the which is known by the quick separation and econd part, or coating, is made up of common escape of the zinc of the brass. A little tube is earth, mixed with horse-dung: this is spread all laid to convey it into an earthenware basio, over the model, and in such thickness as which is fixed over the top of the mould. Into withstand, in some measure, the weight of the this basin all the large branches from the jets enter, and from which is conveyed the metal when drying the core and melting the wax, is into all the parts of the mould. The jets are that which is more particularly sought for ; 10 all stopped up with a kind of plugs, which are do which, in the most effectual way, four walls kept close till the basin which is to supply the of brick-work are built up round the model, in metal be full. When the furnace is first opened the middle of which is fixed the grate and furfor this purpose, the melted brass gushes for- nace; and on one side above is formed the mass ward like a torrent of fire, and is prevented of building intended for the furnace, which is to from entering any of the jets by the plugs, till be appropriated to the melting of the metal. the basin is sufficiently full to be ready to begin When the whole is finished and ready, a fire is with the mould, and which is esteemed so when made in the fire-place under the core of the the brass it contains is adequate to the supply of model, and kept up so as to produce a moderate all the jets at once, upon which occasion the heat to dry the core, and also to melt away the plugs from all of them are withdrawn. The wax from off it, which runs down by tubes as plugs consist of a long iron rod, with a head at has been before remarked upon, and indeed no one end capable of filling the whole diameter of difference whatever takes place in such founding, each tube. The hole in the furnace in which except everything being on a larger scale. the melted metal is contained, is opened with a When the wax is run off, and the fire extinguishlong piece of iron, fitted on the end of a pole to ed in the furnace, bricks are filled in at random, allow of the furnace-man keeping at a distance either into the hole, if founding under ground, from it, as many accidents occur by the red-hot or into the area between the walls if above metal coming in contact with the air, particu- ground; after this is done the fire in the furnace larly if it be damp, in which case the most is again lighted, and blown up and augmented, violent explosions take place. The basin is till such time as both the core and bricks are of filled almost in an instant after the furnace-plug a red-heat; when the fire is again extinguished, is withdrawn, and the metal is then let into the and the whole is left to cool; and when cooled several jets communicating with the model, the bricks are again removed, and all is cleared which when they have emptied themselves into away, and the space again occupied by moistthe shell or mould, the founding is finished, in ened earth to secure and steady the model. as far as the casting is concerned. The rest of the Nothing now remains but running in the metal, work is completed by the sculptor, who takes the which is performed as has been before described new brass figure from out of the mould and earth for smaller foundings of statues. in which it was encompassed, saws off the jets, All the principal cities of ancient Greece and and repairs and restores the parts where re- Rome, boasted of their wealth enumerating quired. His tools for this purpose consist of their statues of brass. Athens, Delphi, and chisels of various sizes, gravers, puncheons, Rhodes, are each reported to have had in and files, &c.
about their temples 3000 brass statues. And In casting colossal statues a somewhat differ- Marcus Scaurus, though an edile only, adorned ent mode is pursued than the one already de- the circus at Rome with upwards of that numscribed: this arises wholly from the size, it being ber of statues of brass, during the time of the found difficult to remove the moulds of such celebrating of the Circensian shows. It afterworks; they are therefore worked and prepared wards, in consequence of this taste continuing to upon the spot where they are to be cast. There prevail at Rome, of forming and collecting are two ways of performing this. By the first works in brass, used to be a proverb among the plan a square bole is dug into the earth some- visitors of that celebrated city,' that in Rome what larger than would be required for the the people of brass were not less numerous than mould, and its sides are hemmed up with brick- the Roman people.' work : at its bottom is formed a hole below the BRONZE, by the Italians called Bronzo, was bottom of the one already prepared, as a fur- well known to the ancients. Egyptians, Greeks, nace, and which must be built up with brick-work, and Romans all made use of it, and that in most having an aperture made outwards into another cases to their important works as connected with pit prepared near it, from which the fuel is put sculpture and the ornamental parts of architecinto the furnace. The top of the furnace in the ture. Bronze was selected by these people as first hole is covered by a grating of iron, and on bearing a finer edge, and not so likely as either this is moulded and placed the case of the statue of its component parts to oxydate by exposure to be cast, and also its waxen coating; in doing to the air: hence they made statues of it to which the same process is observed by the adorn the approaches to their cities and public sculptor as that already described. Near the edifices, affixed it in beautiful and highly relieved edge of the large pit, in which the model is ornaments to the friezes of their temples, cast it placed, is erected the furnace to melt the metal, in basso-relievos to represent the paraphernalia and which is similar to the one already described of their games and festivals, which were retained for common figure-casting, except being of in compartments about their works dedicated to larger dimensions; it has like thai three aper- their gods; and, finally, wrought it into baths, tures, one for putting in the wood, another for tripods, vases, lamps, and other purposes of vent, and a third to run the metal out at. By utility and ornament ; specimens of many of the second plan of founding colossal figures, it which have by its indestructibility come down to is thought sufficient to work the mould above us, as may be seen exhibited in the numerous ground, adopting the same mode with respect to public galleries on the continent, at Rome, a furnace and grate underneath it. For, whether Naples, Florence, and Paris, with some in our under ground or above it, to keep in the heat own Museum. Vol. IX.
The Egyptian bronze consisted, according to over the inside of it, and of the thickness which Basari, of iwo-thirds brass, and one-third cop- it is intended the bronze should be. Within-sid: per.
Pliny says, the Grecian bronze was the clay, a filling up of plaster and brick-dust, formed by adding one-tenth lead, and one- in the proportions as before described, will be twentieth silver, to the two-thirds brass and the required to compose the core: but, if the work one-third copper of the Egyptian bronze,' and to be cast be large, before the plaster and brickthis was the proportion afterwards made use of dust are poured into the mould to form the core, by the Roman statuaries. The Greek bronzes a skeleton composed of iron bars, as a support very obviously appear to possess a difference of for the figure, should be prepared and fixed; composition to any that have been founded after which the filling up of the core may be among the moderns. The famous Venetian horses proceeded in. When this is done, the mouli (four in number), said to have been the work of must be opened again, and the layer of clay Lysippus, exhibit at once, to bronzists, that the taken out of it, and the core thoroughly driet, ancient metal of that name was, in its composi- and even burned with a charcoal fire, or with tion, very different from that which is now made straw; for, if the least damp remain, the cast and called after that designation :—the modern will be blown to pieces when the hot metal comes bronze is commonly made of two-thirds copper, in contact with it, in running it into the mould, fused with one-third of brass ; and very lately, and the workmen employed about the work be from the great demand for all kinds of ornaments maimed or killed by the dispersion of the heated in this metal, in forming the decorative parts to bronze. After the core, &c., has been properly pur apartments, and supports to our articles of dried, and is deemed ready for the work, it furniture, lead, with zinc in small proportions, should be laid in the mould, and supported in have been added to the copper and brass. These its place by short rods of bronze, which should sariations have been one cause of the greater run through the mouid into the core. All being brilliancy and compactness to be observed in so far advanced, the mould should be clad and modern castings of this metal, in comparison of bound round with iron, of strength proportionate those founded a few years since. So common is to the size of the work to be cast; after which, bronze-work become at this time, that every the mould should be laid in a situation for runpetty brass-worker pretends to be an adept in ning in the metal, and must be supported for the founding of this metal; however, nothing is to purpose by bricks, &c. Great care should be be feared in the attempt, as the efforts of such taken that every part be perfectly dried, before bronzists will not carry them beyond the work of any metal be run into the mould; or, as has been
before observed, the most fatal consequences will The alloying of the several metals to form arise to those who may be about the work. A bronze is found to promote in it a readier fusi- channel must be made from the furnace in which bility than is possessed by either of its compo- the melted metal is, in order to its running to the nent parts in their pure metallic state ; and this principal jet of the mould, and with a descent, is a property very much to its advantage in the to promote its flowing rapidly. The jets, furcastings of large works. Modern works in bronze nace, &c. &c., are all contrived, as has been become numerous in proportion to the advance before described, for casting figures in brass. ment in the arts. Bronze-casting is employed In Vesaris's Lives is a chapter on brass-founding; in forming equestrian statues, colossal and other and there are also some very useful observations figures in alto-relievo, to set off and adorn pub- in the Life of Beivenuto Cellin; vide Pliny's lic places. It is competent, when in the hand Natural History. of an artist, of giving a zest to architecture; The smaller works in bronze are founded by inasmuch as by its tint, as well as by the great previously being modelled in wax, to which a variety of the forms it is susceptible of being coating of clay is adapted and dried. made into, it is able to add richness by its oppo- Bronze works are cleaned up and repaired sition, and at the same time it finishes the forms after being founded, in a similar manner to what of those parts of architecture requiring it. See figures in brass are, and with the same kind of BRONZE. In that article we have noticed Mac- tools; but this last touch of perfecting what may queir's mode of casting large works.
have been left imperfect by the mould, should Bronze-casting is also performed in the follow- invariably be done by the statuary or modeller ing manner, viz. 1. The figure or pattern to be cast himself; as no one is so competent to keep up must have a mould, and this is prepared and laid the spirit of the original work, as he who invented on a plaster cast, previously wrought and finished it, and gave effect to his invention, by making the by the sculptor. The mould is made of plaster of model. Paris, rendered moist by being mixed up with The principal works executed in London in water; to this preparation is added brick-dust, bronze, claiming particular hotice, are, the equesin the proportion of one-third of the former to two- trian statue at Charing Cross, of Charles I.; the thirds of the latter. This is carefully laid on the colossal statue of nis late majesty, in the square would, with strength in proportion to the weight of Somerset Place, by the late Mr. Bacon; the of metal intended to be used in the founding. statue of Francis, duke of Bedford, on the south In its joints small channels should be cut tending side of Russell Square: the equestrian statue upwards, and from different parts of the internal of William III., in the centre of St. Jama's hollow, to allow of vent for the air to escape Square, the work of Mr. J. Bacon, jun.; and through, as the heated metal runs in upon the the “Achilles,' in commemoration of Lori mould. A thin layer of clay should be spread Wellington's victories, in Hyde Park. There are also many bronzes of great merit in the pro- ments or inscriptions to be cast upon the bell are vinces.
put. A hole is now dug of an adequate depth The manner of casting Bells is similar to that to contain the mould of the bell, together with of statues, except that the metal is different, the case of it, or cannon, under ground, and there being in bell-metal about one fifth of tin, about six inches below the level of the ground of whereas there is no tin in the brass of statues. the foundry. It must be wide enough to allow The dimensions of the core and wax in mo- of a free passage between the mould and walls, delling a bell, if it be to be one of a ring of or between one mould and another when several several, must formed on a kind of scale or di- bells are to be cast. At the centre of the hole a apason, which will give the height, aperture, stake is erected, which is fixed firmly in the and thickness of the shell necessary to the several ground; this supports an iron peg, on which the tones required. The exterior of the bell is pivot of the second branch of the compasses of formed into rings fashioned into mouldings, and construction turns : these compasses are the chief sometimes inscriptions, mottos, and figures are instruments for making the mould, and consist also added to adorn its exterior; all these are of two legs joined to a third at its apex. The previously modelled and afterwards moulded in stake is surrounded by solid brick-work, of about wax upon the core. The clapper or tongue is not six inches in height and of the diameter of the properly a part of the bell, and is furnished by bell; this is called the mill-stone. The parts other hands; with us it is usually of iron, and is of the mould consist of the core, the model of suspended in the middle of the bell. The Chi- the bell, and the shell. nese make it of wood, leaving a hole under the When the outer surface of the core is formed, cannon of the bell to increase its sound. Our it is raised up with bricks, which are laid in proportions of bells consist in making the di- courses of equal height upon a layer of earth; ameter fifteen times as thick as the brim, and its as each brick is laid the work is brought near to length twelve times. The bell itself consists of the branch of the compasses on which the curve its sounding bow, which is terminated by an in- of the core is shaped, so as that there may referior circle, which diminishes thinner and main between it and the curve the distance of a thinner as it approaches to the brim or that part line, to be afterwards filled up with layers of ceon which the clapper strikes, and which is re- ment. The building of the core is continued to quired to be left rather thicker than the rest both the top, leaving only an opening for the coals to above and belosv; also the outward sinking or be put in to bake the core. This work is covered properly the waist of the bell, or the point under with a layer of cement made of earth and horsewhich it grows wider to the brim; and the upper dung, and on which is moved the compass of vase, or top or dome of the bell, or that part construction, to make it of an even smoothness which is above the waist. The pallet is the in- every where. Having finished the first layer in side of the vase or dome to which the clapper is this way, the fire is put into the core by filling it suspended. The vent and hollowed branches of half with coals through an opening kept shut metal which unite with the cannon to receive the during the baking, and with a cake of earth iron keys by which the bell is hung to its beam which has been separately baked. The first fire of support, where it must be exactly counter- consumes the stake, and it is left in the core a poised. The height of a bell is in proportion to half and sometimes a whole day: the first layer its diameter as twelve is to fifteen, or in the pro- having become thoroughly dry, it is covered with portion of the fundamental sound to its third a second, also a third and fourth, each being surmajor, from which it follows that the sound of a rounded with a board and also the compasses, bell is principally composed of the sound of its and also thoroughly dried before another is proextremity or brim as a fundamental of the sound ceeded on. The core being thus finished, the of the crown, and which is an octave to it, and compasses are taken to pieces with the intention that of the height, which is a third.
of cutting away the thickness of the model, To mould a bell for casting, the following pre- which when done they are again put in their parations must be made. Earth must be col- places to begin another piece of the mould. This lected, and that which is most cohesive is the piece consists of a mixture of earth ana hair best, and it must be well ground and sifted. applied with the hand upon the core in several Brick or stone must be obtained for the mine, cakes, these all close together if properly applied. with which it must be stained. Horse-dung, This part of the work is finished afterwards in hair, and hemp, must be mixed with the earth, several additional layers of cement of the same to render the composition for moulding more matter smoothed by the compasses, and thofirm and binding. The wax to mould the in- roughly dried before another is laid on. The scriptions, coats of arms, and other insignia first layer of the model is a mixture of wax and about the outer surface of the bell: also tallow tallow, which is spread over the whole. must be mixed with the wax in equal propor- When the work has so far proceeded, the tions, to make it mould more freely; when inscriptions or other insignia intended to be cast mixed, a slight layer of the compound is put upon the bell are applied, for doing which a upon the model of outer mould, previously to pencil is used dipped in a vessel of wax melted any of the ornaments being applied to it. A in a chafing dish; this is done for every letter, scaffold is raised upon tressels round the mine, or figure intended to be upon the bell. Before upon which is placed the earth grossly diluted the shell is begun, the compasses are taken to with water, to make it mix better with the dung; pieces, in order to cut away all the wood that and, last of all, shelves are to be placed, on fills the place of the thickness which is intended which the models, &c., of the different orna. to be given to the shell. When this is done and