Abbildungen der Seite
PDF
EPUB

all is clear, the shell is begun, the first layer of voids in the mould. The shell being thus unwhich is the same earth sifted very fine. While loaded of its rings, the mill-stone is arranged by it is tempering with water, it is mixed up with having placed under it five or six pieces of wood cow-hair to make it cohere; the whole, being a of about two feet long, and thick enough to reach third cullis, is gently poured on the model, and almost to the lower part of the shell; between fills exactly all the sinuosities of the figures; and these and the mould wooden wedges are driven, in this is repeated till the whole is two lines in order to shake the shell from off the model, so thickness upon the model; when these layers are as to be pulled away and removed up out of the properly dried they cover it with a second of the pit. When this and the wax are removed, the same matter, but somewhat thicker than those model and layer of earth are arranged for the previously laid on; the compasses are now tried founding, as it is through these the melted metal and a fire is lighted in the core, so as to melt off must pass into the hollows made by the rings, the wax of the inscription, &c.; after which the and which are between the shell and core. The layers of the shell are proceeded in by means of inside of the shell is last of all dried by burning the compasses. There is now to be added to the straw under it, this helps to smooth the surface composition a quantity of hemp, which is spread of the bell. The shell is put in the place so as upon the layers and afterwards smoothed upon to leave the same interval between it and the the board of the compasses. The shell varies core as was before; and before the hollows of from four to five inches lower than the mille the rings on the cap are put on again two vents stone before observed, but surrounds it quite are made, which are united to the rings, and also close, and prevents the extravasation of the me- to each other, by a mass of baked cement; after tal. The wax should be taken out before melt- which this mass of the cap is put on, the rings ing the metal. The case of the bell requires a and the vent over the bell are soldered to the cap separate work, which is done during the drying by cement; which is dried by gradual heat by of the several incrustations of the cements. It covering it with burning coals. So much having has seven rings; the last is called the bridge, been done, the pit surrounding the whole is filled and united to the others, it being a perpendicular up with earth, being pressed strongly all the time support to strengthen the curves. It has an of putting in close round the mould. aperture at its top to admit an iron peg and bent The furnace has a place for the fire and anoat its bottom, and this is introduced into two ther to contain the metal; the fire-place has a holes in the beam fastened with two strong iron large chimney with a spacious ash-hole. The keys. The rings are modelled with masses of furnace which contains the metal is vaulted, and beaten earth, that are dried in the fire in order its bottom is made of earth rammed down, the to have them hollow. The rings are gently rest is built of brick-work. It has four apertures, pressed upon a layer of earth and cow-hair to the first of which admits the flame projected by about one half of their depth, and then taken the fire to reverberate, the second is closed by a out, and care should be taken not to break the stopple, which is opened for the metal to run mould. This operation is repeated twelve times through; the other two are to separate the dross for twelve half moulds, that is, two and two and scoriæ by allowing the attendant of the furunited make the hollow of the six rings; the nace to introduce a wooden rake through it for same is done for the hollow of the bridge. They the purpose. These apertures also pass the thick are all united together upon the open place left smoke. The ground or floor of the furnace is for the coals to be put into the oven. The rings built sloping for the metal to run down. When which are to form the ears are put first into this the metal is fused and ready to fill the shell, which open place, with the iron ring to support the should be examined minutely in every part to see clapper of the bell. After which a round cake if it be dry and ready to receive it; when all is of clay is make to fill up the diameter of the deemed ready, the metal is suffered to run into thickness of the core. This cake after having the shell by the apertures prepared to admit it, been baked is placed upon the opening, and fas- after which it is allowed to fix and cool. It is tened by a thin mortar spread over it, which then taken out, examined, and cleaned, in a sibinds the cover close to the core. The hollow milar manner to what has been before explained of the mould is filled with an earth sufficiently for brass and bronze castings. moist to fix itself on the place which is strewed The theory of the sound of bells is noticei in at several times upon the cover of the core; it is our article of that name; together with several then beaten gently with a pestle, and afterwards curious facts of their history. See Bell. smoothed.by a workman at top with a wooden The method of forming the profile of a bell, trowel dipped in water. Upon this cover, which previous to its being cast, in which the proporis afterwards to be taken off, is assembled the tion of the several parts may be seen, is as folhollow of the rings; and, when every thing is in lows: the thickness of the brim C1, of the diaits proper place, the outside of the hollows are gram, is the foundation of every other measure, strengthened with mortar, in order to bind and is divided into three equal parts. First, them to the bridge and keep them steady, and at draw the line HD, which represents the diameter the bottom by means of a cake of the same mor- of the bell; bisect it in F, and erect the perpentar, and which fills up the whole aperture of the dicular Ff; let D F and HF be also bisected shell. This is left to dry, that it may afterwards in E and G, and two other perpendiculars El, be removed without breaking. To make room Ga, be erected at F and G; G E will be the for the heated metal, the rings are taken out of diameter of the top or upper vase, i. e. the diathe hollows in the mould, as it is in these hol- meter of the top will be half that of the bell ; lows that the metal is to pass as it enters into the and it will, therefore, he the diameter of a bell

[ocr errors][ocr errors][merged small]

whicn will sound an octave to the other. Divide with the radius C1, describe the arc 1 pn; blthe diameter of the bell, or the line HD, into sect the part 1 2, of the line D n, and, erecting fifteen equal parts, and one of these will give Ci the perpendicular p m, this perpendicular will the thickness of the brim : divide again each of cut the arc 1pn in m, which terminates the these fifteen equal parts into three other equal rounding 1 p. Some founders make the bendparts, and then form a scale. From this scale ings, K, a third of a brim lower than the middle take twelve of the larger divisions or 2-15ths of of the line DN; others make the part C1D the whole scale in the compass, and setting one more acute, and instead of making C 1 perpenleg in D describe an arc to cut the line Ee in N; dicular to D N at 1, draw it out one-sixth of a draw ND, and divide this line into twelve equal brim higher, making it still equal to one brim; parts; at the point 1 erect the perpendicular so that the line 1 D is longer than the brim C1. ic=10, and C 1 will be the thickness of the In order to trace out the top part, Na, take in brim = 1-15th of the diameter; draw the line the compass eight divisions of the scale or eight CD; bisect DN; and at the point of the bisec- brims; and on the points N and D as centres, tion 6, erect the perpendicular 6 K=13 of the describe arcs to intersect each other in 8: on this larger divisions on the scale. With an opening point 8, with a radius of eight brims, describe the of the compass equal to twice the length of the arc Nb; this arc will be the exterior curve of the scale, or thirty brims, setting one leg in N, top or crown; on the same point 8 as a centre, describe an arc of a circle, and with the same and with a radius equal to 73 brims, describe leg in K, and the same opening, describe another the arc Ae, and this will be the interior curve of arc to intersect the former : on this point of the crown, and its whole thickness will be oneintersection as a centre, and, with a radius equal third of the brim. As the point 8 does not fall to thirty brims, describe the arc 'NK; in 6K in the axis of the bell, a centre M may be found produced take K B=} of the larger measure of in the axis by describing, with the interval of the scale or one-third of the brim, and on the eight brims on the centres D and H, arcs which same centre with the radius 30brims describe will intersect in M; and this point may be made an arc AB parallel to NK, For the arc BC, the centre of the inner and outer curves of the take twelve divisions of the scale or twelve brims crown as before. The thickness of the cap, which in the compass; find a centre, and from that strengthens the crown at Q, is about one-third centre, with this opening, describe the arc BC, of the thickness of the brim; and the hollow in the same manner as N K or A B were described. branches or ears about one-sixth of the diameter There are various ways of describing the arc Kp, of the bell. The height of the bell is in proporsome describe it on a centre at the distance of tion to its diameter as twelve to fifteen, or in the nine brims from the points p and K; others, as proportion of the fundamental sound to its third it is done in the figure, on a centre at the dis- major; whence it follows that the sound of a bell tance only of seven brims from those points. is principally composed of the sound of its exBut it is necessary first to find the point p, tremity or brim, as a fundamental of the sound and to determine the rounding of the bell p 1. of the crown which is an octave to it, and of that For this purpose, on the point C as a centre, and of the height which is a third.

FOUND'LING, n. s. From found, of find. A child exposed to chance; a child found without any parent or owner.

A piece of charity, practised by most of the nations about us, is a provision for foundlings, or for those children who are exposed to the barbarity of cruel and unnatural parents.

Addison.
The goddess long had marked the child's distress,
And long had sought his sufferings to redress;
She prays the gods to take the foundling's part,
To teach bis hands some beneficial art. Gay.

FOUNT, n. s. ) Lat. fons, from fundo,
Foun'tain, n. s. to pour out, and signi-
Foun’TAINLESS, adj. (fies the spring which is

FOUNTFUL, 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,

Id.

The wanting orphans saw with wat'ry eyes foundation; but he who endows it with lands is Their founder's charity in the dust laid low. the founder: and to the erection of an hospital,

Dryden. nothing else is requisite but the incorporation For zeal like bers, her servants were to show ;) and foundation. Persons seised of estates, in She was the first, where need required to go

fee-simple, may found hospitals for the poor by Herself the foundress and attendant too.

deed enrolled in chancery, &c., which shall be I draw a line along shore;

incorporated, and subject to such visitors as the

founder shall appoint, &c. stat. 39 Eliz. c. 5. I lay the deep foundations of a wall, And Enos, named from me, the city call. Id.

FOUND, v. a. Fr. fondre, fondeur ; Lat. When Jove, who saw from high, with just disdain, Found'er, n. s. fundere. To form by meltThe dead inspired with vital breath again,

FOUND'RY, n.

s ing and pouring into Struck to the centre with his flaming dart

moulds; to cast. A founder is the agent, and The unhappy founder of the godlike art. Id. foundry is the casting-house or place of his opeNor was Præneste's founder wanting there,

ration." Whom fame reports the son of Mulciber. Id.

A second multitude They Gabian walls, and strong Fideuæ rear.

With wondrous art founded the massy ore, Nomentum, Bola with Pometia found,

Severing each kind, scummed the bullion dross. And raise Colatian towers on rocky ground. Id.

Milton. That she should be subject to her husband, the Founders add a little antimony to their bell-metal, laws of mankind and customs of nations have ordered to make it more sonorous ; and so pewterers to their it so ; and there is a foundation in nature for it. pewter, to make it sound more clear like silver. Locke.

Grew's Museum, A right to the use of the creatures is founded originally in the right a man has to subsist.

- FOUNDERS, persons who cast metals in va

d. Power, founded on contract, can descend only to tous

o rious forms and for different uses; as guns, bells, him who has a right by that contract.

id. statues, printing characters, candlesticks, bucKing James I. the founder of the Stewart race, had kles, &c., whence they are denominated gunhe not confined all his views to the peace of his own founders, bell-founders, figurereign, his son had not been involved in such fatal founders, letter-founders, fountroubles.

Addison's Freeholder. ders of small works, &c. The

nourable founder of this lecture in his treatise of the corporated in 1614. Their arms air.

Bentley. are azure, an ewer between two Ne'er to these chambers where the mighty rest, pillars, or, as in the annexed diaSince their foundation, came a nobler guest. Tickel. gram.

The reputation of the Iliad they found upon the FOUND'ER, v. a. & v. n. Fr. fondre ; It. fond, ignorance of his times. Pope's Preface to the Iliad.

the bottom. To cause such a soreness and tenNor can the skilful herald trace

derness in a horse's foot, that he is unable to set The founder of thy ancient race. Swift. He had an opportunity of going to school on a

. it to the ground. To sink to the bottom; to fail; foundation.

Id. to miscarry. The first foundation of friendship is not the power

Out of the ground, a fury infernal sterte, of conferring benefits, but the equality with which

From Pluto sent, at requeste of Saturne ;

For which his hors for fere gan to turne, they are received, and may be returned.

Junius's Letters.

And lepte aside, and foundred as he lepe. Gregory the Seventh, who may be adored or de.

Chaucer. The Knightes Tale. tested as the founder of the Papal monarchy, was

Phæbus' steeds are foundered, driven from Rome, and died in exile at Salerno.

Or night kept chained below.
Gibbon.

Shakspeare Tempest.

In this point Foundation, in architecture. See ARCHI

All his tricks founder; and he brings his physick TECTURE, Index. Palladio allows a sixth part After his patient's death. Id. Henry VIII. of the lieight of the whole building for the New ships, built at those rates, have been ready to hollowing or under-digging, unless there be cel- founder in the seas with every extraordinary storm. lars under ground, in which case he would have

Raleigh's Essays. it somewhat lower.

EL. BR.

For certain, FOUNDATION, in law, denotes a donation or Either some one, like us, night-foundered here, legacy, either in money or lands, for the main- Or else some neighbour woodman, or at worst tenance and support of some community, hos

Some roving robber calling to his fellows. Milton. pital, school, &c. The king only can found a

A bear will not attempt to fly; college, but there may be a college in reputation founded by others. If it cannot appear by in

A foundered horse will oft debate,

Before he tries a five-barred gate. Swift. quisition who founded a church or college, it

The roar shall be intended that it was the king, who has of breakers has not daunted my slight trim, power to found a new church, &c. The king But still sea-worthy skiff, and she may boat may found and erect an hospital, and give a Where ships have foundered, as doth many a buat. name to the house upon the inheritance of an

Byren. other, or license another person to do it upon To FOUNDER, in sea language, is used, when his own lands; and the words fundo, creo, &c., a ship, by an extraordinary leak, or by a great are not necessary in every foundation, either of sea breaking in upon her, is so filled with water a college or hospital, made by the king; but it that she cannot be freed of it; so that she can is sufficient if there be words equivalent; the neither veer nor steer, but lies like a log; and not incorporation of a college or hospital is the very being able to swim long, will at last sink.

493

FOUND IN G.

FOUNDING, in the mechanical arts, will strictly indented sana must be a perfect cameo of the include castings in brass and bronze, the found- models submitted and pressed into it. If it ing of cannon, all the other operations of the should not be found perfect, new sand must be iron foundry, and bell and type founding. But added, and the inodel re-indented and pressed, some of these are of sufficient importance to re- till it leaves its impression in a state proper to quire distinct treatment.

receive the metal. In the same manner, other For the founding of cannon, see GUNNERY. models intended to be founded on the same ta

For the operations of the iron foundry, see ble, must be prepared and indented into the Iron FOUNDRY.

sand. When the table is completely ready for For type-founding, see TYPE.

the metal, it is carried to the melter, who himThis paper will be confined to founding in self examines its state, and also the cameos, brass and bronze; and to bell founding.

and who lays along the middle of the mould the Brass is a compound of copper and zinc, half of a small wire of brass, which he presses which become, by being fused together, a homo- into the sand, so as to form a sinall channel for geneous malleable yellow metal, of great utility the melted brass to flow in, and which he terms in various articles of our domestic economy, and the master-jet or canal. It is so disposed as to in the arts, in which it is also employed in the meet the ledge on one side, and far enough to founding of statues, &c. &c. See Brass. reach the last pattern on the other; from this are

Founders of brass articles of a general de- made several less jets or branches, extending scription require an exact model, in wood or themselves to each pattern on the table, and by otherwise, of the article to be founded; and this which means the Auid metal is conveyed to all is most frequently required to be in two parts, the different indented impressions required to be exactly joined together, and fitted by small pins: cast on the table. When the work is so far forthe casting, in such a case, is performed by two warded, it is deemed ready for the foundry; operations, that is, one half at one time and one previously to which, however, the whole is half at another, and in manner following, viz. sprinkled over with mill-dust, and when it is so The founder provides himself with a yellowish sprinkled, the table is placed in an oven of mosharp sand, which is required to be well washed, derate temperature till it gets dry, or in a state to free it of all earthy and other particles. This which is deemed proper to receive the melted saud is prepared for use by a process called brass. tewing, which consists in working up the sand The first table being thus far completed, it is in a moist state, over a board about one foot either turned upside down and the moulds or square, wbich is placed over a box to receive patterns taken out, or the moulder begins to prewhat may fall over in the tewing. A roller pare another table exactly similar to the one he about two feet long and two inches in diameter has just completed, in which he indents and is employed in rolling the sand about until it is presses the other half of the mould, or he turns brought into that state which is deemed proper the table already finished and containing the for its business: a long-bladed knife is also re- first half of the patterns upside down; previquired to cut it in pieces. With the roller and ously, however, to doing which, it will be nethe knife the tewing is finished for use, by being cessary for him to loosen the pattern which is alternately rolled and cut. When the sand is so fixed in the sand a little all round, with any far prepared, the moulder provides himself with small instrument that will just open away the a table or board, which in size must be regulated sand from its edges, in order to its coming from by the castings about to be performed on it. out of the table more easily. This economy in The edges of the table or board are surrounded founding, of making one-half of each pattern by a ledge, in order to support the tewed stuff; to be cast answer the purpose of the whole patthe table so previously prepared is filled up with tern, is a very common practice in brass foundthe sand as high as the top of the ledge, which ing, and enables the manufacturer to sell his goods is in a moderately moistened state, and which at a much cheaper rate than he would otherwise must be pressed closely down upon the table in be enabled to do, if he were obliged to have a every part. When the operation has so far ad- full pattern of all goods to be founded. When vanced, the models must be all examined, to see he has loosened the sand from about the pattern, that they are in a state to come picely out of the and taken it out of the first table, the work is mould, and if not found so, they must be cleaned proceeded in, of preparing the counterpart or or altered till the founder is satisfied with them. other half of the mould with the same pattern, All models require the greatest accuracy in their or otherwise, and in a frame exactly correspondmaking, or it will be vain to suppose any thing ing with the former, excepting only that it is good can be performed by the founder.

prepared with small pins, to enter holes which When the models are found to be in a state to are made in the first half of the model, and into be founded, one half, generally longitudinally, is which the pins enter, and secure the two halves taken first, and this is applied on the mould, and together. It is obvious, that the accuracy in the pressed down into the tewed stuff or sand, so as joining will depend wholly upon the neatness to leave its form completely indented in it: this and truth of fixing and boring for the pins. must be very carefully looked to, to see that. When the table containing the counterpart is there are no small holes; as every part in the finished, the patterns are all properly indented in the sand, which is done as has been before cible, into which the fresh brass is dropped from described for the first table, and when com- out of the cylindrical arm of the iron ladle. As pleted, it is carried away to the melter, who, the crucible is filled with metal, preparation after enlarging the principal jet of the counter- must be made, when it is deemed ready to be part, and making the cross jets to the various removed for the purpose of running it into the patterns, sprinkles them as before with mill- moulds, to remove it easily from out of the fire, dust : it is then set in the oven till it has re- which is done by a pair of iron longs with their ceived a sufficient drying to be ready for the feet bent inwards. The crucible is taken hold melted metal; after which, and when both parts of by these tongs, and carried away to the of the model are deemed sufficiently dry, they mould, into which the melted brass is poured, are joined together by means of the pins and through the aperture communicating to the masholes, previously prepared in the upper and un- ter-jet of each mould; the metal is carried der model : and to prevent their rising up or round to each jet, and poured in till the cruslipping aside by the force of the melted brass, cible is emptied, or the moulds filled. It is which is to come in flaming with heat, and usual to fuse rather more brass than is required through a small hole contrived in the principal for the casting; as, by having too little, the work or master-jet, the precaution is taken of locking could not be at that time finished, which would the two tables down in a kind of press made occasion delays in opening the tables. As soon with screws; or, if the mould be too large to as the moulds are run, water is sprinkled over admit of being screwed easily, wedges are had the tables, to cool and fix the metal ; after which recourse to, to fix the tables together, to prevent the presses or wedges are removed from the accidents. The moulds thus fixed in the press, frames, and the works just founded are removed or wedged, are placed near the furnace, and out of the sand, to be cleaned and finished for every arrangement is made for it to receive the sale. The tewing-stuff or sand is afterwards melted brass as it comes out of the crucible. taken out of the frames to be worked up again

All being so far arranged, and the moulds for another casting. The sand, by a repetition ready, the metal is prepared, by being heated to of use, becomes quite black, by reason of the a complete fusion in an earthen crucible, com- charcoal that it collects from the foundry; but monly about ten inches high and four inches in its blackness does not render it unfit to be diameter. The furnace for promoting the fusion employed in other tables for moulding or castof the brass is similar to a smith's forge, having ing. bellows of large dimensions operated upon by a In foundings of brass in which the models are lever, and a chimney over the furnace. The large, an expedient is had recourse to, of redhearth is of masonry or brick-work, secured by dering them lighter and more economical, by an outer rim of iron, in the centre of which is performing the casting hollow. This is done by the fire-place, and which consists in making a making a core or heart, roughly resembling the voiu or cavity, from twelve to eighteen inches pattern, and composed of clay and white cruci. square, and reaching quite down to the bottom ble dust well kneaded and mixed together with or floor of the foundry. The void or cavity is water, and which is covered with wax, exactly divided into two parts by an iron grating, on the representing the article to be cast; or the core upper side of which is placed the fuel, and in may be suspended in the centre of the indents the midst of it the crucible containing the me- made in the sand. When the article is required tal; the lower part of the cavity is appropriated to have but one perfect side, as is common in to admit the air to the fire, and also to receive most cabinet articles, the melted metal, in such the waste or cinders falling from the fire. The a case, is prevented from filling the indent by the fuel consists of dry beechen wood cut into small space occupied by the core, and it will be in billets, and previously baked, to make them thickness corresponding to the size which the more readily combustible, and which are, when heart or core takes up, in proportion to the size a fire is required, put into the cavity in the of the work to be founded. In the former case, hearth, and well lighted. The crucible, when when the article is to bave both or all round of full of brass, should be placed down in the a full pattern, wax is employed, and is so adcentre of the fire, so that it may play all round justed to the core, that the metal may, in passing it, and it should be covered with an earthen co- the jet, displace it, and leave its resemblance, ver, or tile, to promote the heat of the fire upon and also its thickness, of brass, in the indent in the metal. All the time the metal is preparing, the table. If it be a pattern of a complicated the attendant keeps blowing up the fire; and in form, there would arise a difficulty in getting the order to keep the heat from escaping through the core out after it was founded. The pattern must chimney, or in flame, a piece of tile is placed then be performed or moulded in two separate over the fire and aperture of the furnace. As ones, and also the foundings; the part left out the heat operates in melting the metal, it sinks of the first pattern must be performed in a senearer to the bottom of the crucible, when fresh cond; and afterwards fitted and soldered to the metal is added till the crucible is quite full. The first. This mode is common at Birmingham, in brass is previously prepared for melting, by be- making handles for locks, and shutter fastenings, ing broken into small fragments in a mortar, which are commonly round. The plain knobs, and, when sufficiently beaten and broken for use, for locks, &c., are made in halves and soldered it is put into the crucible by an iron ladle, which together: the wrought ones, as they are called has a long hollow arm or shank of small dia- from being ornamented) are cast with a solid meter, but sufficiently large to admit the frag- shank and spindle, and the bell or handle part ments of metal rolling through it into the cru- of the knob is hollow, and open at its opposite

« ZurückWeiter »