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ENCYCLOPÆDIA PERTHENSIS.

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FOUNDERY.

of metal uniting with the cannons, to receive the As the conclusion of our last Volume, (see page iron keys, whereby the bell is hung up to the beam,

718,) we inserted this word in its proper order, wbich is its fupport and counterpoife, when rug with its different definitions, but had not fuffi

out. The business of beil-foundery is reducible cient room remaining in that volume to insert the

to three particulars. i. The proportion of a bell, various branches of this art, in the complete

2. The forming of the mould And, 3, The mel. manner, which an article of such importance ting of the metal. There are two kind of prorequired.

portions, viz. the fimple and the relative; the

former, are those proportions only that are beYOUNDERY OF Bells. The metal, it is to tween the several parts of a bell to render it fonois for ftatues; there being no tin in the latter ; but quifite harmony between several beils. The methere is a sth, and sometimes more, in the bell-me. thod of forming the profile of a bell, previous to tal. The dimenfions of the core and the wax for its being cast, in which the proportion of the sea bells, if a ring of bells especially, are not left to veral parts may be seen, is as follows: the thickchance, but must be measured on a scale, or diapa- ness of the brim, Ci, Plate CLV. fig. 12. is the fon, which gives the height, aperture, and thick- foundation of every other meafure, and is divided nels, neceliary for the several tones required. It is into three equal parts. First, draw the line HD, on the wax that the several mouldings and other or which represents the diameter of the bell; bifect naments and infcriptions, to be represented in re- it in F, and erect the perpendicular Pf; let DF and levo on the outside of the bell, are formed. The HF be also bifected in E and G, and two other clapper or tongue is not properly a, part of the perpendiculars E é, G a, be erected at F and G; bell, but is furnished from other hands. In Eu- Ge will be the diameter of the top of upper vale, rope, it is usually of iron, with a large knob at i.e. the diameter of the top will be half that of the extremity; and is fufpended in the middle of the bell; and it will, therefore, be the diameter the belle in China, it is only a huge wooden of a bell which will found an o&ave to the other. mallet, ftruck by force of arm against the bell; Divide the diameter of the bells or the line HD, inwhence they can bave but little of that confonan. to 15 equal parts, and one of these will give Cs ay so much admired in some of our rings of beils. the thickness of the brim : divide again each of The Chinese have an extraordinary way of increa- these 15 equal parts into three other equal parts, ang the sound of their bells, viz. by leaving a hole and then form a fcale. From this scale iake 12 of under the capoon;'which our bell founders would the larger divisions or two 15ths of the whole scale reckon a défeat. The proportions of our bells in the compass, and setting one leg in D describe differ very much from those of the Chinese, as an arc to cut the line E e in N; draw ND, and well as their fizes. See Bell, No 1, § 5. In ours, divide this line into's 2 equal parts; at the point the modern proportions are, to make the diame. i erect the perpendicular C=10, and Ci will ter 15 times the thickness of the brim, and the be the thickness of the brim =one 15th of the height 12 times. The parts of a beil are, 1. diameter; draw the line CD: bisect DN; and The founding bow, terminated by an inferior cir- at the point of the bisection 6 erect the perpendia cle, which grows thinner and thinner. 2. The cular 6 K=Ij vf the larger divisions on the scale. brim or that part of a tell whereon the clapper With an opening of the compafs equal tp twice Atrikes, and which is thicker than the reit. 3. the length of the scale or 30 brims, setting one leg The outward finking of the middle of the bell, or in N, describe an arc of a circle, and witn the fime the point under which it grows wider to the brim. leg in K and the same opening, describe another 4. The waist or furniture, and the part that grows arc to interfect the former : on this point of im wider and thicker quite to the brim. 5. The up- tersection as a centre, and with a radius equal to per vase, or that part which is above the waist. 30 brims, describe the arc NK; in 6 K produced 6. The pallet which supports the staple of the fake KB= } of the larger measure of the scale or clapper within. 7. The bent and hollow branches of the brim, and on the same centre with the VOL. X. PART I.

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radius

radius 30; brims deferibe an arc AB parallei to contist of two diferent legs, joined by a thir3 NK. For the arc BC, take 12 divifions of the piece. And last of all, the founders shelver, cu scale or 12 brims in the compass ; find a centre, which are the engravings of the letters, cartridges, ard from that centre, with this opening, describe coats of arms, &c. They first dig a hole of a the arc pc, in the fame manner as NK or AB sufficient depth to contain the mould of the bell, were deliribed. There are various ways of de- together with the case or cannon, under ground; seribing the arc Kp; fome describe it on a centre and about fix inches lower than the terreplain, at the distance of nine brims from the points p where the work is performed. The hole must be and K; others, as it is done in the figure, on a wide enough for a free passage beiween the mould centre at the distance only of leven brinis from and walls of the hole, or between one mouid those points. But it is neceflary first to find the and another, when several bells are to be caft. point P, and to determine the rounding of the At the centre of the hole is a stake erected, that is bell p i. For this purpose, on the point C as a strongly fastened in the ground. This supports centre, and with the radius C i, describe the aro an iron peg, on which the pivot of the second ipn; bifect the part 1, 2, of the line D n, and branch of the compafles turns. The fake is en. erecting the perpendicular p m, this perpendicu- compaffed with a solid brick work, perfectly round, lar will cut the arc 1 p nin m, which terminates about half a foot high, and of the proposed beli'n the rounding i p. Some founders make the bend. diameter. This they call a mill fione. The party i?K a third of a brim lower than the middle of of the mou'd are, the core, the model of the bull, the line DN; others make the part C i D more and the shell. When the outer surface of the core acute, and instead of making Ci perpendicular is formed, they begin to raift the corr, which is to DN at 1, draw it one 6th of a brim higher, made of bricks that are laid in courses of equal making it Rill equal to one brim; so that the line height upon a lay of pain earth. At the lasing 1 D is longer than the brim C!. In order to irace of each brick, they bring near it the branches of out the top part Na, take in the compass eight the con pafles, on which the curve of the core is divisions of the scale or 8 brims, and on the points shaped, so as that there may remain between it N and D as centres, describe arcs to interfect and the curve the distance of a line, to be, after. each other in 8 : on this point 8, with a radius of wards filled up with layers of cement. The work eight brims, describe the ark Nb; this arc will be is continued to the top, only leaving an opening the exterior curve of the top or crown; on the for the coals to bake the core. This work is cofame point 8 as a centre, and with a radius equal vered with a layer of cenient, made of earth and to y brims, defcribe the arc A e, and this will horse-dung; on which they move the compaffles be the interior curve of the crown, and its whole of construction, to make it of an even smoothoela thickness will he one third of the brim. As the every where. The firít layer being finished, they point 8 does not fall in the axis of the bell, a put the fire to the core, by filling it half with coals, centre M may be found in the axis by describing, through an opening that is kept shut during the with the interval of 8 brims on the centres D and baking, with a cake of earth that has been fopa. ll, arcs which will interfect in M; and this point rately baked. The first fire consumes the fake, may be made the centre of the inner and outer and the fire is left in the core half or sometimes a curves of the crown as before. The thicknefs of whole day: the first layer being thoroughlý drs, the cap, which strengthens the çrown at l, is about they cover it with a second, third, and fourth ; one third of the thickness of the brim; and the each being smoothed by the board of the compar. bollow branches or ears about one fixth of the ses, and thoroughly dried before they proceed to diameter of the bell. The height of the bell is in another. The core being completed, they take proportion to its diameter as 12 to 1s, or in the compasses to pieces, with intent to cut off the the proportion of the fundamental sound to its thickness of the model, and the companes are third major: whence it follows that the sound of immediately put in their place to begin a fecom! a bell is principally composed of the found of its piece of the mould. It consists of a mixture of extremity or brim, as a fundamental of the found earth and hair, applied with the hand of the of the crown which is an octave lo it, and of that core, in several cakes that close together. This of the height which is a third. The particulars work is finished by several layers of a thinner ceneceffary for making the mould of a bell are, 1. ment of the same matter, smoothed by the comThe-earth: the most cohesive is the best ; it must paffes, and 'thoroughly dried before another is be well ground and lifted, to prevent any chinks. laid on.' The first layer of the model is a mixture 2. Brick stone; which must be used for the mine, of wax and grease spread over the whole. Aftp mould, or core, and for the furnace. 3. Horse-dung, which are applied the infcriptions, coats of arm, hair, and hemp, mixed with the earth, to render &c. besmeared with a pencil dipped in a vetiel of the cement more binding. 4. The wax for infcrip- wax in a chafing dish: this is done for every lettes, Lions, coats of arins, &c. 5. The tallow equally Before the fell is begun, the compasses are fåken mixed with the wax, in order to put a Night lay to pieces, to cut off all the wood that fills the of it upon the outer mould, before any letters are place of the thickness to be given to the thell

. applied to it. 6. The coals to dry the mould The first layer is the same earth with the re, For making the mould they have a scaffold con- sifte: very fine ; whilst it is tempering in water, listing of four boards, ranged upon treffels. Upon it is mixed with cow's hair to make it cobert, this they carry the earth, grossiy diluted, to mix The whole being a thin cullis, is gently prureul it with horse-dung, beating the whole with a large on the model, that fills exa&tly all ihe finuofitius (pru11. The compafles of confruction are the of the figures, &c. and this is repeated till the chief instrument for making the mould: They whole is iwo lines thick over the model. When

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this layer is thorougi.iy dried, they cover it with a earth, through which the metal nut run, from #econd of the same matter, but somewhat thicker; the hollow vi the rings, between the Mell and the when this second layer becomes of some conhf. core. They, sinoke ine inside of the thell, by tence, they apply the compafles again, and light burning Araw under it, that helps to smooth the a tin in the core, so as to melt off the wax of the surface of the bell. Then they put the thell in the inscriptions, &c. After this, they go on with the place, so as to leave the fame interval between otlier lay?is of the hell, by means of the coin- that and the core; and before the hollows of the patles. Here they add to the cow's hair a quan. rings or the cap are put on again, they ndu two tity of hemp, spread upon the layers, and after- vents, that are united to the rings, and to cach wards imouthed by the board of the compasses. other, by a mats of baked cement. After which The thickness of the shell comes to 4 or 5 inches they put on this mass of the cap, the rings, and lower than the mill ftone before obferied, and lur- the vent, over the meli, and folder it with thin rounds it quite close, which prevents the extra- cement, which is cried gradually by covtring it vafation of the metal. The wax thould be taken with burning coals. Then they fill up the pit out before the melting of the metal. The ear of with earth, beating it ftrongly ail the time round the bell requires a separate work, which is done the mould. The surface has a ; iace for life during the drying of the several incrustations of and another for the metal. The fire place has a cement. It has g rings: the 7th is called the large chimney with a spacious ath-hole. The furbridgs, and unites the others, being a perpendi- nace which contains the metal is vaulted, whose calar lupport to strengthen the curves. It has an bottom is made of earth, rammed down; the rest aperture at the top, to admit a large iron peg, is built with brick. it has four apertures; the bent at the bottom; and this is introduced into firît, through wrich the plane revertirates; the fetwo holes in the beam, faftened with two strong cond is cloied with a stopple that is opened for fron keys. There are models made of the rings, the metal to run; the others are to separate the with maties of beaten earth, that are dried in the drofs or scoriæ of the metal by wooden rakes: fire, in order to have the hollow of them. These through these last apertures palie's the thick furoke. rings are gently pressed upon a layer of earth and the ground of the furnace is built Doping, for €ws' hair, one half of its depth: and then taken the metal to run down. out, without breaking the mould. This opera. 2. FOUNDERY OF GREAT CUNS AND MORTAR tion is repeated 12 times for 12 half moulds, that PIECES. The method of casting these pieces is tward two united may make the hollows of the different from that of bells: they are run maliy, ha rims; the fame they do for the hollow of the without any core, being determined by the holLiege, and bake them all, to unite them together. low of the hell; and they are afterwards bored Upon the open place left for the coais to be put with a steel trepan, that is worked either by hortis in, are placed the rings that constitute the ear. or a water mill. For the metal, parts, propor. They first put into this open place the iron ring tions, &c. of these pieces, fue GUNNERY. to fupport the clapper of the bell; then they make 3. FOUNDERY OF LEITEPS, OR CASTING OF a romd cake of clay, to fill up the diameter of TYPES FOR PRINTING. In the business of cutthe chickness of the core.' This cake, after ba- ting, cafting, &c. letters for printing, the letter-cutting, is clapped upon the opening, and sol'ered ter muit be provided with a vice, hand-vice, hamwith a thin mortar spread over it, which binds mers, and files of all sorts such as watch-makers the cover close to the core. The hollow of the use; also gravers and sculpters of all forts, and model is filled with an earth, fufficiently moil to an oil-fione, &c. suitable and sizeable to the letefix on the place, which is strewed at several times ral letters to be cut; a fiat gauge made of box to upon the cover of the core; and they beat it gent. hold a rod of steel, or the body of a mould, &c. ly with a peftle, to a proper height; and a work- exactly perpendicular to the Hat of the uting file; man fmooths the earth at top with a wooden a sliding gauge v huse use is to measure and set off trowel dipped in water. Upon this cover, to be distances between the shoulder and the tooth, and taken off afterwards, they afsemble the hollows to mark off from the end, or from the edge of of the rings. When every thing is in its proper the work; a face gauge, which is a square notch place, they itrengthen the outside of the hollows cut with a file into the edge of a thin plate of with mortar, in order to bind them with the steel, iron or brass, of the thickness of a piece of britze, and keep them steady at the bottom, by common tin, whofé use is to proportion the face of means of a cake of the same mortar, which filis each sort of letter, viz. long letters, afcending up the whole aperture of the shell. This they let letters, and Mort letters So there must be 3 gauges, dør, that it may be removed without breaking, and the guage for the long letters is the length

To make room for the metal, they pull off the of the whole body supposed to be divided into hollows of the rings, through which the metal is 42 equal parts. The gauge for the afcending let. ta pals, before it enters into the vacuity of the ters Roman a: d Italic are five yths, cr 30 parts of mruld. The shell being unloaded of its ear, they 42, and 33 paits for the English face. I he galęc range under the mill-fone five or fix pieces of for the most letters is three 7ths, or 18 parts of wood, about two feet long, and thick enough to 42 of the whole ludy for the Ronian and Italic, reach almost the lower part of the shell; between and 22 parts for the English face. The Italic and these and the mould, they drive in wooden wedges other standing gauges are to measure the fcope of with à maliet, to ihake the fhell of the model the Italic Items, by applying the top and bottom

beroon it reits, fo as to be pulled up and got of the gauge to the top and bottom lines of the setout of the pit. When this and the wax are re. ters, and the other fire of the gauge too!-!{m; tored, they break the model and the layer of for when the letter complies with these three fidea

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of the gauge, that letter has its true shape. The them with their heads to the feet of the other half; next care of the letter cutter is to prepare good

and if then the heads and the feet be found ex. steel punches, well tempered, and quite free from actly even upon each other, and neither to drive all veins of iron; on the face of which he draws out nor get in, the two sides may be prenounced or marks the exact thape of the letter with pen paraliei. He farther tries whether the two lides and ink if the letter be large, or with a smooth of the thickness of the letter be parallel, by fi:ft blunted point of a needle if it he finall; and then setting his proofs in the compoling ftick with their with sizeable and proper shaped and pointed gra- nicks upwards, and then turning one half with vers and sculpters, digs or fculps out the feel their heads to the feet of the other half; and if between the frokes or marks he made on the face the heads aud feet lie exadly upon each other, of the punch, and leaves the marks Aanding on and neither drive out nor get in, the two fides of the face. Having well thaped the infide ftrokes the thickness are parallel. The mould thus juftiof his letter, be deepens the hollows with the same fied, the next butiness is to prepare the matrices. tools; for if a letter be not deep in proportion to A matrice is a piece of brals or copper of about its width, it will, when used at press, print black, an inch and a half long, and of a thibkness in proand be good for nothing. This work is generally portion to the fize of the letter it is to contain. regulated by the depth of the counter-punch. In this metal is sunk the face of the letter intendThen he works the outside with proper files till ed to be caft, by striking the letter punch about it be fit for the matrice. Before we proceed to the depth of an n. After this the sides and face the finking and justifying of the matrices, we muit of the matrice must be justified, and cleared with provide a mould to justify them by. See Plate files of all bunchings made by firking the punch. CLV. Fig. 13, and 14. Every mouid is compof- Every thing thus prepared, it is brought to the ed of an upper and an under part. The under furnace; which is built of brick upright, with 4 part is delineated in fig. 13. The upper part is fquare fides, and a stone on the top, in which marked fig. 14. and is in all respects made like the stone is a wide round hole for the pan to starid in, under part, excepting the ftool behind, and the A founder y of any extent his several of tiefe turbow or ipring also behind, and excepting a small naces in it. As to the metal of which the types roundith wire between the body and carriage, are to be caft, this, in extentive founderies, is uear the break, where the under part hath a small always prepared in large quantities; but caft into rounding groove made in the body. This wire, small bars, of about 20 pounds weight, to be deor rather bulf-wire, in the upper part makes the livered out to the workmen as occasion requires. nick in the Mauk of the letter, when part of it is in the letter foundery, which has been long carreceived into the groove in the under pirt. These ried on with reputation under the direction of two parts are so exactly fitted and gauged into one Dr Alex. Wilson and fons at Glasgow, we are inanother viz. the male.gauge marked c in fig. 14. formed, that a stock of nietal is made up at tuo into the female marked g in fig. 13.) that when the different times of the year, sufficient to serve the upper part of the mould is properly placed on, caliers at the furnace' for six months each time. and in the under part of the mould, both together for this purpose, a large furnace is built under a make the entire mould, and may be lid back. Thade, furniihet with a wheel vent, in order the wards for use fo far, till the edge of either of the more equally to heat the fides of a ftrong pot of bodies on the middle oi either carriage comes juit cast iron, which holds when full 15 Cut. of the to the edge of the female gauges cut in each care metal. The fire being kindled below, the bars riage; and they may be lid forw' rd so far, till of lead are let softly down into the pot, and their the bodies on either carriage touch each other: fusion proir oted by throwing in some pitch and and the Niding of these two parts of the mould tallow, which foon inflame. An outer chimney, backwards makes the thank of the letter thicker, which is built so as to project about a foot over because the bodi's in each part ftand wider afun- the farthest lip of the pot, catches hold of the der; and the siding them forwards makes the frame by a strong draught, and makes it act very Thank of the letter thinner, because the bodies on powerfully in melting lead; whift it serves at the each part of the mould are as follow: viz. a, fame time to convey away all the fumes, &e. from

e carriage. b, The body.' c, The male gauge the workmen, to whom this laborious part of the de, The mouth-piece. fi, The register. The buhness is committed. When the lead is the female gange. h, The bag. a a o a, The bottom roughly melted, a due proportion of the regu us platė. 6 bob, The woud on which the bottom or antimony and other ingredients are put in, and piate lies. ccc, The mouth. dd, The throat, lome more tallow is enfamed to make the whole <dd, The pallat. f, The nick. 88, The ftool. incorporate foower. The workmen, having mishl, The spring or bow. Then the mould musted the contents of the pot very thoroughly by be justified: and first the founder justifies the stirring long with a large iron ladle next proceed body, by cafting about 20 proofs or samples of to draw the metal off into the small troughs of letters; which are set up in a composing stick, cast iron, which are ranged to the number of 80 with all their nicks towards the right tand; and upon a leve' platform faced with ftune, built tothen by comparing these with the pattern leiters, wards the right hand. In the course of a day 15 let up in the same manner, he finds the exact mea. Cwt. of metal can be eafily prepared in this manifure of the body to be cast. He also tries if the ner; and the operation is continued for as many two sides of the body are parallel, so that'the body days as are necítary to prepare a stock of metal be no bigger at the head ihan at the foot, by do of all the various degrees of bardness. After this, ng half the number of his proofs and turning the whole is ditzuled into prelles according to its

quality, to be deivered out occasionally to the

workmen.

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