FOUNDERY. 



beat It gently with a pestle to a proper 

 height ; and a workman smooths the 

 earth at top with a wooden trowel dipped 

 in water. 



Upon this cover, to be taken off after- 

 wards, they assemble the hollows of the 

 rings. When every thing is in its pro- 

 per place, they strengthen the outsides 

 of the hollows with mortar, in order to 

 bind them with the bridge, and keep 

 them steady at the bottom, by means of a 

 cake of the same mortar, which fills up 

 the whole aperture of the shell. This 

 they let dry, that it may be removed with- 

 out breaking. To make room for the me- 

 tal, they pull off the hollows of the rings 

 through which the metal is to pass, be- 

 fore it enters into the vacuity of the 

 mould. The shell being unloaded of its 

 ear, they range under the mill-stone five 

 or six pieces of wood, about two feet 

 long, and thick enough to reach almost 

 the lower part of the shell; between these 

 and the mould they drive in wooden 

 wedges with a mallet, to shake the shell 

 of the model whereon it rests, so as to be 

 pulled up, and got out of the pit. 



When this and the wax are removed, 

 they break the model and the layer of 

 earth, through which the metal must run, 

 from the hollow of the rings, between the 

 bell and the core. They smoke the in- 

 side of the shell, by burning straw under 

 it, that helps to smooth the surface of 

 the bell. Then they put the shell in 

 the place, so as to leave the same interval 

 between that and the core ; and before 

 the hollows of the rings or the cap are 

 put on again, they add two vents, that are 

 united to the rings, and to each other, by 

 a mass of baked cement. After which 

 they put on this muss of the cap, the 

 rings, and the vent, over the shell, and 

 solder it with thin'cement, which is dried 

 gradually, by covering it with burning 

 coals. Then they fill up the pit with earth, 

 beating it strongly all the time round 

 the mould. 



The furnace has a place for the fire, 

 and another for the metal. The fire- 

 place has a large chimney, with a spa- 

 cious ash-hole. The furnace, which 

 contains the metal, is vaulted, whose bot- 

 tom is made of earth, rammed down ; 

 the rest is built with brick. It has four 

 apertures ; the first, through which the 

 flame reverberates ; the second is closed 

 with a stopple, that is opened for the me- 

 tal to run ; the others are to separate the 

 dross, or scoriae, of the metal by wooden 

 rakes : through these last apertures pass- 



VOL. V. 



es the thick smoke. The ground of the 

 furnace is built sloping, for the metal to 

 run down. 



FOUNDER Y, of great guns and mortar- 

 pieces. The method of casting these 

 pieces is little different from that of bells; 

 they are run massy, without any core, be- 

 ing determined by the hollow of the shell; 

 and they are afterwards bored with a steel 

 trepan, that is worked either by horses or 

 a water-mill or steam. 



FOUNDER?, Letter, or casting of printing 

 types. The first thing requisite is to pre- 

 pare good steel punches, on the face of 

 which is drawn the exact shape of the 

 letter with pen and ink, if the letter be 

 large ; or with a smooth blunted point of 

 a needle, if small; and then, with proper 

 gravers, the cutter digs deep between the 

 strokes, letting the marks stand on the 

 punch; the work of hollowing being ge- 

 nerally regulated by the depth of the 

 counter punch : then he files the outside^ 

 till it is fit for the matrice. 



They have a mould to; justify the ma- 

 trices by, which consists of an upper and 

 under part; both these are alike, ex- 

 cept the stool and spring behind, and a 

 small roundish wire in the upper part, 

 for making the nick in the shank of the 

 letter. These two parts are exactly fit- 

 ted into each other, being a male and fe- 

 male gage, to slide backwards and for- 

 wards. 



Then they justify the mould, by cast- 

 ing about twenty samples of letters, which 

 are set in a composing stick, with the 

 nicks towards the right hand ; and com- 

 paring these every way with the pattern 

 letters, set up in the same manner, they 

 find the exact measure of the body to be 

 cast. 



Next they prepare the matrice, which 

 is of brass or copper, an inch and a half 

 long, and of a proportionable thickness 

 to the size of the letter it is to contain. 

 In this metal is sunk the face of the let- 

 ter, by striking the letter-punch the depth 

 of an n. After this, the sides and face of 

 the matrice are justified, and cleared, 

 with files, of all bunchings that have been 

 made by sinking the punch. 



Then it is brought to the furnace, 

 which is built upright of brick, with four 

 square sides and a stone at top, in which 

 is a hole for the pan to stand in. They 

 have several of these furnaces. 



Printing-letters are made of lead, hard- 

 ened with iron or stub-nails. To make 

 the iron run, they mingle an equal weight 

 of antimonv, beaten small in an iron mor- 



Ee 



