642 



PRINTING 



In Moxon's time, in 1683, it will be seen that there were only ten types with specific 

 names, whereas, we have now twenty-one. 



The materials from which types and stereotype-plates are cast are technically called 

 metal, and consist of certain proportions of lead, tin, and antimony, melted together. 

 Until recently, types were always cast in little moulds held in the hands, the melted 

 metal being poured in from a small ladle ; but now they are thrown off with great 

 rapidity by machinery. The type-casting machine consists of a mould, constructed so 

 as, by means of a crank, to open for the purpose of letting the type drop out, and then 

 to shut together again very closely and exactly ; the opening and shutting being per- 

 formed every time the crank is turned once round. Each time the crank revolves, and 

 is brought up to the furnace-mouth (a small orifice not much larger than a pin-hole), 

 and takes a supply of metal. This metal is driven by a force-pump in a reservoir, 

 worked by the crank, into the mould, and the type is formed. The types are then 

 rubbed smooth upon stones ; set up, or arranged in rows, for inspection by the dresser, 

 who carefully examines them, and rejects those which are bad, giving the perfect ones 

 the finishing touch. The most complete process is, perhaps, that of Messrs. Johnson 

 and Atkinson. A double line of grooves is placed side by side. At one end is a 

 reservoir of molten lead, to which the mould is brought ; a jet of metal is thrown into 

 the mould, which then opens, and deposits the type on a travelling apparatus in the 

 groove. As the groove fills, it is impelled along, and in its progress, the shanks are 

 taken off. At the end, the position of the type is reversed by the machinery into the 

 returning "groove, in which it is rubbed, dressed, has the bottoms planed, and the nicks 

 cut. On arriving at the exit end of the groove, it is received into a type-founder's 

 stick, which has to be removed as it is filled, and the type is then ready for packing. 

 The great advantage in type-machines consists in the increased facility of production. 

 One machine and one man in ten hours will produce 30,000 brevier types (or 60 Ibs.), 

 the size used for this work, while by hand-labour only 5,000 (or 10 Ibs.,) could be 

 cast in the same time. 



Messrs. Miller and Richards, of Edinburgh and London, employ not less than eighty 

 steam type-casting machines, equalling in production the labour of 480 men. 



Number of Lines of the different-sized Types contained in One Foot. 



The beauty of type depends upon the delicacy with which the matrix, or mother- 

 type, js formed. This mould is a short thick bar of copper, with the form of the letter 

 intended to be produced stamped on one side of it (fig. 1671). The letter of the 

 matrix is stamped in by means of a punch, a small piece of steel, a letter cut upon 

 one end, and the other end a flat head to receive the blow of a hammer (fig. 1672). 



The length of the body of a type is called its height to paper ; and this, unfortunately, 

 is not uniform, there being a London and a Scotch height, the former not so high as 

 the latter. 



