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FOUNDING.

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 With as much as three-quarters of an inch. 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 eniployed 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 orna-
ments used as decorations to chimney-pieces
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, moder-
ately 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 tinc-
ture 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 com-
pletely 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 In preparing mould or core, so called from being in the middle or heart of the statue. 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 lessen 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 horsedung 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 cir cumstances 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. 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 je

This last aperture

FOUNDING.

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.

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 There upon the spot where they are to be cast. 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 fur-
nace; 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 extinguish-
ed 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 moist-
ened 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.'

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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

500

FOUNDING.

all is clear, the shell is begun, the first layer of which is the same earth sifted very fine. While it is tempering with water, it is mixed up with cow-hair to make it cohere; the whole, being a third cullis, is gently poured on the model, and fills exactly all the sinuosities of the figures; and this is repeated till the whole is two lines in thickness upon the model; when these layers are properly dried they cover it with a second of the same matter, but somewhat thicker than those previously laid on; the compasses are now tried and a fire is lighted in the core, so as to melt off the wax of the inscription, &c.; after which the layers of the shell are proceeded in by means of the compasses. There is now to be added to the composition a quantity of hemp, which is spread upon the layers and afterwards smoothed upon the board of the compasses. from four to five inches lower than the millThe shell varies stone before observed, but surrounds it quite close, and prevents the extravasation of the metal. The wax should be taken out before melting the metal. The case of the bell requires a separate work, which is done during the drying of the several incrustations of the cements. has seven rings; the last is called the bridge, It and united to the others, it being a perpendicular support to strengthen the curves. It has an aperture at its top to admit an iron peg and bent at its bottom, and this is introduced into two holes in the beam fastened with two strong iron keys. The rings are modelled with masses of beaten earth, that are dried in the fire in order to have them hollow. The rings are gently pressed upon a layer of earth and cow-hair to about one half of their depth, and then taken out, and care should be taken not to break the mould. This operation is repeated twelve times for twelve half moulds, that is, two and two united make the hollow of the six rings; the same is done for the hollow of the bridge. They are all united together upon the open place left for the coals to be put into the oven. which are to form the ears are put first into this The rings open place, with the iron ring to support the clapper of the bell. After which a round cake of clay is make to fill up the diameter of the thickness of the core. This cake after having been baked is placed upon the opening, and fastened by a thin mortar spread over it, which binds the cover close to the core. of the mould is filled with an earth sufficiently The hollow moist to fix itself on the place which is strewed at several times upon the cover of the core; it is then beaten gently with a pestle, and afterwards smoothed by a workman at top with a wooden trowel dipped in water. Upon this cover, which is afterwards to be taken off, is assembled the hollow of the rings; and, when every thing is in its proper place, the outside of the hollows are strengthened with mortar, in order to bind them to the bridge and keep them steady, and at the bottom by means of a cake of the same mortar, and which fills up the whole aperture of the shell. This is left to dry, that it may afterwards be removed without breaking. To make room for the heated metal, the rings are taken out of the hollows in the mould, as it is in these hollows that the metal is to pass as it enters into the

voids in the mould. loaded of its rings, the mill-stone is arranged by The shell being thus unhaving placed under it five or six pieces of wood almost to the lower part of the shell; between of about two feet long, and thick enough to reach these and the mould wooden wedges are driven, in order to shake the shell from off the model, so pit. When this and the wax are removed, the as to be pulled away and removed up out of the model and layer of earth are arranged for the founding, as it is through these the melted metal must pass into the hollows made by the rings, and which are between the shell and core. The inside of the shell is last of all dried by burning straw under it, this helps to smooth the surface of the bell. The shell is put in the place so as to leave the same interval between it and the the rings on the cap are put on again two vents core as was before; and before the hollows of are made, which are united to the rings, and also which this mass of the cap is put on, the rings to each other, by a mass of baked cement; after by cement; which is dried by gradual heat by and the vent over the bell are soldered to the cap been done, the pit surrounding the whole is filled covering it with burning coals. So much having up with earth, being pressed strongly all the time of putting in close round the mould.

ther to contain the metal; the fire-place has a
The furnace has a place for the fire and ano-
large chimney with a spacious ash-hole. The
furnace which contains the metal is vaulted, and
its bottom is made of earth rammed down, the
rest is built of brick-work. It has four apertures,
the fire to reverberate, the second is closed by a
the first of which admits the flame projected by
stopple, which is opened for the metal to run
through; the other two are to separate the dross
and scoriæ by allowing the attendant of the fur-
the purpose. These apertures also pass the thick
nace to introduce a wooden rake through it for
smoke. The ground or floor of the furnace is
the metal is fused and ready to fill the shell, which
built sloping for the metal to run down. When
should be examined minutely in every part to see
if it be dry and ready to receive it; when all is
deemed ready, the metal is suffered to run into
the shell by the apertures prepared to admit it,
after which it is allowed to fix and cool. It is
then taken out, examined, and cleaned, in a si-
for brass and bronze castings.
milar manner to what has been before explained

our article of that name; together with several
The theory of the sound of bells is noticed in
curious facts of their history. See BELL.

previous to its being cast, in which the propor-
The method of forming the profile of a bell,
tion of the several parts may be seen, is as fol-
lows: the thickness of the brim C 1, of the dia-
and is divided into three equal parts.
gram, is the foundation of every other measure,
draw the line HD, which represents the diameter
of the bell; bisect it in F, and erect the perpen-
First,
dicular Ff; let D F and HF be also bisected
in E and G, and two other perpendiculars Ee,
Ga, be erected at F and G; GE will be the
diameter of the top or upper vase, i. e. the dia-
meter of the top will be half that of the bell;
and it will, therefore, be the diameter of a bell

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which will sound an octave to the other. Divide the diameter of the bell, or the line HD, into fifteen equal parts, and one of these will give C1 the thickness of the brim: divide again each of these fifteen equal parts into three other equal parts, and then form a scale. From this scale take twelve of the larger divisions or 2-15ths of the whole scale in the compass, and setting one leg in D describe an arc to cut the line Ee in N; draw N D, and divide this line into twelve equal parts; at the point 1 erect the perpendicular iC10, and C 1 will be the thickness of the brim 1-15th of the diameter; draw the line CD; bisect DN; and at the point of the bisection 6, erect the perpendicular 6 K=1 of the larger divisions on the scale. With an opening of the compass equal to twice the length of the scale, or thirty brims, setting one leg in N, describe an arc of a circle, and with the same leg in K, and the same opening, describe another are to intersect the former: on this point of intersection as a centre, and, with a radius equal to thirty brims, describe the arc 'N K; in 6 K produced take KB = { of the larger measure of the scale or one-third of the brim, and on the same centre with the radius 30 brims describe an arc A B parallel to NK. For the arc BC, take twelve divisions of the scale or twelve brims in the compass; find a centre, and from that centre, with this opening, describe the arc BC, in the same manner as N K or A B were described. There are various ways of describing the arc Kp, some describe it on a centre at the distance of nine brims from the points p and K; others, as it is done in the figure, on a centre at the distance only of seven brims from those points. But it is necessary first to find the point p, and to determine the rounding of the bell p 1. For this purpose, on the point C as a centre, and

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with the radius C 1, describe the arc 1pn; bisect the part 1 2, of the line Dn, and, erecting the perpendicular pm, this perpendicular will cut the arc 1pn in m, which terminates the rounding 1 p. Some founders make the bendings, K, a third of a brim lower than the middle of the line DN; others make the part C1D more acute, and instead of making C 1 perpendicular to DN at 1, draw it out one-sixth of a brim higher, making it still equal to one brim; so that the line 1 D is longer than the brim C1. In order to trace out the top part, Na, take in the compass eight divisions of the scale or eight brims; and on the points N and D as centres, describe arcs to intersect each other in 8: on this point 8, with a radius of eight brims, describe the arc N 6; this arc will be the exterior curve of the top or crown; on the same point 8 as a centre, and with a radius equal to 73 brims, describe the arc Ae, and this will be the interior curve of the crown, and its whole thickness will be onethird of the brim. As the point 8 does not fall in the axis of the bell, a centre M may be found in the axis by describing, with the interval of eight brims on the centres D and H, arcs which will intersect in M; and this point may be made the centre of the inner and outer curves of the crown as before. The thickness of the cap, which strengthens the crown at Q, is about one-third of the thickness of the brim; and the hollow branches or ears about one-sixth of the diameter of the bell. The height of the bell is in proportion to its diameter as twelve to fifteen, or in the proportion of the fundamental sound to its third major; whence 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 which is an octave to it, and of that of the height which is a third.

FOUNT, n. s. FOUNTAIN, n.s.

Lat. fons, from fundo, to pour out, and signiFOUNTAINLESS, adj. (fies the spring which is FOUNT FUL, adj. visible on the earth. A well; a spring; whether natural or artificial: a jet; a spout of water: the head or first spring of water; hence, metaphorically, original; first principle; first cause. The adjectives are in direct opposition as to meaning.

Unkindnesse past they gan of solace treat, And bathe in pleasaunce of the joyous shade,

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