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STEREOTYPE. 



Firman Didot, the celebrated French printer, 

 sometime afterwards applied the stereotype art to 

 logarithmic tables, and then to some of the Latin 

 classics, as well as to a number of French publica- 

 tions. His original method of stereotyping differed 

 much from that now in use. He took movable 

 letters, differing from the common ones only by 

 being somewhat shorter, and of a harder substance. 

 These were set in the usual way ; the proof sheets 

 were then printed and corrected, till the whole 

 copy was as free from errors as possible. Then 

 every page set with these hard letters was pressed 

 upon a plate of properly prepared metal. These 

 plates served as matrices for whole pages; and the 

 letters of the hard substance, mentioned above, 

 might now be separated from each other, set anew, 

 and used to form other matrice- plates. A page 

 which served for a matrice was pressed upon melted 

 type-metal, which, hardening immediately, served 

 for printing. In this manner was Callet's logarithmic 

 tables printed in 1795. 



To the patronage of earl Stanhope the art of 

 stereotyping is greatly indebted for its improvement 

 and general adoption in this country. It is said 

 that his lordship was instructed in the mystery by 

 Mr Tilloch, and afterwards had, at his estate of 

 Chevening, the personal attendance of Mr Foulis 

 for several months. Mr Wilson, a respectable 

 printer in London, engaged with earl Stanhope, 

 some years after this, in prosecuting experiments 

 towards the improvement of the art ; and in 

 January, 1804, Mr Wilson laid before the university 

 of Cambridge the result of their experiments in 

 stereotyping, with offers to execute by stereotype 

 the Cambridge bibles, testaments, and prayer books. 

 Some difference, however, arose between the syndics 

 of the university and Mr Wilson, on which occasion 

 the latter published his case in a stereotyped pam- 

 phlet, entitled, " Arbitration between the university 

 of Cambridge and Andrew Wilson." 



By degrees, the benefits of stereotyping began to 

 be understood, and within the last twenty years, it 

 has come to be adopted in the production of nume- 

 rous works, particularly standard authors, for whom 

 there is a continued demand, and works published 

 in parts or numbers. In the case of a book in 

 general use, such as the Bible, and also in cases 

 where the publication takes place in numbers, and 

 one number is in danger of being sold to a greater 

 extent than another, stereotyping is of vast utility. 

 It may, indeed, be pronounced absolutely necessary 

 to the production of cheap books in large numbers, 

 and therefore a most important auxiliary in the dif- 

 fusion of knowledge by the printing-press. It 

 saves the publisher from printing more copies at a 

 time than may be required, or from the necessity 

 of anew composition of types for every new demand. 

 In some cases, too, by casting more plates than one, 

 the same work may be printed in different parts of 

 the world at the same time, without the cost of a 

 different composition of types for each place, and 

 so as to avoid the carriage of printed sheets from 

 one quarter to another. 



We shall now briefly describe the process of 

 stereotyping, as at present generally practised. 

 Stereotyping is distinctly superadded to the work 

 of printing from movable types (described under 

 Printing'), and forms a middle operation between 

 the labours of the compositor and the pressman. 

 The first point in stereotyping is that of taking a 

 mould from each page of movable types. The 

 pages are not arranged as they would be combined 



in a sheet, and wedged up together in one iron 

 frame or chase, but each page is put in a separate 

 chase. It is essential that the face of the types 

 should he perfectly clean and dry, and that no par- 

 ticle of dirt or other substance should attach to the 

 bottom of the types, so as to prevent them being 

 level upon the surface. The page is now placed 

 upon the lower part of a moulding-frame. The 

 upper part of the frame is somewhat larger than the 

 page, and the margin of mould thus formed deter- 

 mines the thickness of the plates. The types 

 having been previously rubbed over with an oily 

 composition, plaster of Paris is poured evenly over 

 the whole surface. This substance, from a liquid 

 state, soon becomes perfectly solid. Much nicety 

 is required from the workman, in forming the 

 mould, and in removing it from the type. If any 

 part of the plaster adheres to the face of the type, 

 the mould is imperfect, and the operation must be 

 gone over again. Having been removed and found 

 perfect, it requires some dressing with a knife on 

 its edges, and several notches are cut in the margin 

 to allow the metal to enter the mould. It is now 

 fit for baking. This process also requires much 

 care. The oven in which the moulds are placed 

 must be kept at a very regular temperature; for if 

 it be too hot, the moulds warp. The process of 

 casting begins when the moulds have been baked 

 sufficiently long to be perfectly dry and hard. At 

 the bottom of the pot is a movable plate of cast- 

 iron, called a floating-plate; and upon this plate 

 the mould is placed with its face downwards. 

 Upon the back of the mould rests the cover of the 

 casting-box, which is held tightly down upon the 

 mould by a screw. The apparatus for plunging the 

 casting-box into the metal pit is attached to a crane, 

 and is so constructed as to swing with a perfectly 

 horizontal motion. The casting-pot, with the 

 mould, being suspended over the metal pot, is 

 gradually forced down into the metal, and there 

 kept steady by a lever and weight. The lid of the 

 casting-box is cut off at the corners; and it is 

 through these spaces that the metal enters the box, 

 and insinuates itself into every hollow. After 

 having remained immersed for about ten minutes, 

 it is steadily lifted out by the crane, and swung to 

 a cooling trough, in which the under side of the 

 box is exposed to water. Being completely cooled, 

 the workman proceeds to remove the mould from 

 the casting-box. The plaster-mould, the plate 

 moulded, and the floating-plate, are all solidly fixed 

 together. The metal, by its specific gravity, has 

 forced itself under the floating-plate, which it has 

 driven tightly up against the ledges of the mould. 

 The mould has in the same way been tightly driven 

 up against the lid of the casting-box. The notches 

 in the ledges of the mould have, at the same time, 

 admitted the metal into the minutest impression 

 from the face of the types. The caster or workman 

 now breaks off the superfluous metal and the ledges 

 of the mould with a wooden mallet. The mould 

 is necessarily destroyed ; and if another plate is re- 

 quired, another mould must be taken from the types. 

 After the superfluous metal and the plaster are 

 removed, the stereotype plate comes out, and is 

 then prepared for the press. Its proper thickness 

 cannot be determined by the mould alone; and the 

 back of the plate is therefore turned in a lathe, in 

 which the plate revolves against a cutting tool, and 

 a perfectly true surface is obtained by the super- 

 fluous parts being cut away in a series of concentric 

 circles. Besides this, the very best casting cannot 



