The surface of a page of types cast in one piece, of type metal, about the eighth of an inch thick, and turned in a lathe at the back of the plate, so that the whole of the plates of a volume shall be of one uniform thickness.
When they are required to be printed they are mounted on what are called Risers: these risers, with the thickness of the stereotype plate, are precisely the same height as the types, so that when a form is composed of stereotype plates and types, the pressure shall be equal on both. — See Risers.
The spaces and quadrats are cast higher than for the common process; and when the form is ready, the face of it is oiled with a brush, then burnt plaster of Paris (gypsum) mixed with water to the consistence of cream is poured upon it; when the plaster is sufficiently hardened It is taken off from the types and forms a matrix in which to cast a fac-simile of the types; this matrix is then placed in an oven to dry, and made hot, when it is secured in a frame and immersed in a caldron of melted metal, where it remains some time; when it is taken out, and cool, it goes to a person styled the Picker, to remove any superfluous metal, and to remedv any defects; it is then, generally, turned at the back to a specific thickness, and to remove any inequalities; after this it is ready for press. For the details of the process I refer the reader to “An Essay on the Origin and Progress of Stereotype Printing: including a Description of the various Processes. By Thomas Hodgson, Newcastle: printed by and for S. Hodgson, &c. 1820.”
This process was first practised by William Ged, of Edinburgh, who commences in the year 1725. After much perseverance he formed an engagement with the University of Cambridge to print Bibles and Prayer-books; but the plan received so much opposition from the workmen, in making errors and batters, that it was discontinued, and the plates were ultimately sent to Mr. Caslon's foundery to be melted down. Mr. Hansard, in his Typographia, says, — “But a remnant escaped from Caslon's cormorant crucible; and I have the opportunity of here presenting my readers with an opposite view of a pair of the very malefactors; and challenge any other to dispute the palm of venerable antiquity with them: they have been rather roughly treated, but besides the purpose for which they are here exhibited, will serve to show the style of type, typography, and stereotype of those days.”
Mr. Tilloch had a page of Ged's casting given to him by Mr. Murray, of Fleet Street, bookseller, which I have seen: there is also a plate of Ged's casting, at the Royal Institution, containing fourteen pages of a Common Prayer, presented by Mr. Frederick Kanmacher, of Apothecaries Hall, from which I had impressions printed.— See “Biographical Memoirs of William Ged. By John Nichols.” 8vo. London, 1781. “Dissertation upon English Typographical Founders and Founderies, by Edward Rowe Mores, A. M. and A. S. S.”