TYPE 



1049 



copper dissolved in ammonia, finely-powdered calcined ivory. They are allowed to 

 remain together for about a week, at a moderate heat. The coherent mass is dried 

 and exposed to a gentle heat. 



TUSSII.AGO. The herb Coltsfoot (Tussilago farfara). 



TUTEKTAG- or TUTEWAGTTE, sometimes called Chinese silver. It is tho 

 Packfong of the East Indies. A white metal of the Chinese, frequently stated to bo 

 an alloy of copper and zinc. It is, in fact, a compound resembling German silver : 

 nickel, in combination with zinc and copper, is found in most specimens 



TUTOKTITE. See EXPLOSIVE AGENTS. 



TYMP, in metallurgy, a rectangular casting of iron, placed upon the tymp-arch at 

 the top of the hearth of a blast-furnace. When it has a wrought-iron tube in its 

 interior through which cold water circulates, it is then called a ' water-tymp.' 



TYPE. (Caractere, Fr. ; Druckbuchstabe, Grer.) The first care of the letter- 

 cutter is to prepare well-tempered steel punches, upon which he draws or marks the 

 exact shape of the letter, with pen and ink if it be large, but with a smooth blunted 

 point of a needle if it be small ; and then, with a proper sized and shaped graver and 

 sculpter, he digs or scoops out the metal between the strokes upon the face of tho 

 punch, leaving the marks untouched and prominent. He next works the outside -with 

 files, till it be fit for the matrix. Punches are also made by hammering down the 

 hollows, filing up the edges, and then hardening the soft steel. Before he proceeds 

 to sink and justify the matrix, he provides a mould to justify them by. 



A matrix is a piece of brass or copper, about an inch and a half long, and thick in 

 proportion to tho size of the letter which it is to contain. In this metal the face 

 of the letter intended to be cast is sunk, by striking it with the punch to a depth 

 of about one-eighth of an inch. The mould, Jig. 2068, in which the types are cast, is 

 composed of two parts. The outer part is made of wood, 

 the inner of steel. At the top it has a hopper-mouth, a, 

 into which the fused type-metal is poured. The interior 

 cavity is as uniform as if it had been hollowed out of a 

 single piece of steel ; because each half, which forms two 

 of the four sides of the. letter, is exactly fitted to the other. 

 The matrix is placed at the bottom of the mould, directly 

 under the centre of the orifice, and is held in its position 

 by a spring, b. Every letter that is cast can be loosened 

 from the matrix only by removing the pressure on the 

 spring. 



A good type-foundry is always provided with several 

 furnaces, each surmounted with an iron pot containing the 

 melted alloy, of 3 parts of lead and 1 of antimony. Into 

 this pot the founder dips the very small iron ladle, to lift 

 merely as much metal as will cast a single letter at a time. 

 Having poured in the metal with his right hand, and 

 returned the ladle to the melting-pot, the founder throws 

 up his left hand, which holds the mould, above his head, 

 with a sudden jerk, supporting it with his right hand. 

 It is this movement which forces the metal into all the interstices of the matrix ; for 

 without it, the metal, especially in the smaller moulds, would not be able to expel 

 the air and reach the bottom. The pouring in the metal, the throwing up the 

 mould, the unclosing it, removing the pressure of the spring, picking out the cast 

 letter, closing the mould again, and reapplying the spring to be ready for a new 

 operation, are all performed with such astonishing rapidityand precision, that a skilful 

 workman will turn out 500 good letters in an hour, being at the rate of one every eighth 

 part of a minute. A considerable piece of metal remains attached to the end of the 

 type as it quits the mould. There are nicks upon the lower edge of tho types, to 

 enable the compositor to place them upright without looking at them. 



From the table of the caster the heap of types turned out of his mould is trans- 

 ferred from time to time to another table, by a boy, whose business it is to break off 

 the superfluous metal, and this he does so rapidly as to clear from 2,000 to 5 000 types 

 in an hour ; a very remarkable despatch, since he must seize them by their edges, 

 and not by their feeble flat sides. From the breaking-off boy the types are taken to 

 the rubber, a man who sits in the centre of the workshop with a grit-stone slab on a 

 table before him, and having on the fore and middle finger of his right hand a piece 

 of tarred leather, passes each broad side of the type smartly over tho stone, turning 

 it in the movement, and that so dexterously as to be able to rub 2,000 types in an hour. 



From the rubber the types are conveyed to a boy, who with equal rapidity sets them 

 up in lines, in a long shallow frame, with their faces uppermost and nicks outwards. 

 This frame containing a full lino is put into the dresser's hands, who polishes them 



