Ottley, in his “Invention of Printing,” was the chief exponent of this theory. He believed that type were made by pouring molten lead into molds of clay or plaster, after the ordinary manner used from time immemorial in casting statues and other articles of metal.
The imperfections in the type cast by the sand and clay processes—the difficulty of uneven heights in the various type—is supposed to have been surmounted either by locking up the form with the type-face downward on the composing stone, or by perforating the type, either at the time of casting or afterwards, and holding them in their places by means of a wire or thread through the perforations.
To this cause has been attributed the numerous misprints in those early specimens of the printers’ art, to correct which would have involved the unthreading of every line in which a typographical error occurred.
A striking proof that the lines were put into the form one by one, as a piece, instead of type by type, is shown in a blunder in the “Speculum” of Coster where the whole of a last reference line is “turned.” It is as if a modern linotype slug were put in the form up-side-down.
A third suggestion as to the method by which the type of those early days of printing may have been produced is described as a system that the type-founders of about 1800 called Polytypage, which is a cast facsimile copy of an engraved block of type matter. Lambinet, who is responsible for this suggestion, explains that this method really means an early adoption of the stereotyping process.
Lambinet thought that the early printers may have discovered a way of molding in cooling metal so as to get a matrix-plate impression of an entire page. Upon this matrix they would pour molten lead or tin and by the aid of a roller, press the fused metal evenly so as to make it penetrate into all the hollows and corners of the letters. This tablet of lead or tin, when cooled, being easily detached from the matrix, would then reveal the letters of the alphabet reversed and in relief, similar to a present day stereotype. The individual letters, of course, could easily be cut apart by a sharp tool, and the molding operation could be repeated, using the same matrix. The metal type faces so produced would be fixed on wooden shanks, type high, and the font would be complete.
It is impossible to suppose, however, that the Mainz psalter of 1457, which Lambinet points to as a specimen of this mode of execution, is the impression, not of type at all, but a collection of “casts” mounted on wood.
Yet another theory has been proposed by Dr. Ch. Enschede, head of the celebrated type foundry of that name in Haarlem. Enschede concludes that the Costerian type were produced from leaden matrices and the latter from brass patrices. Their bad, irregular condition was due to the tools being imperfect, and Coster in the first practice of his invention was inexperienced and therefore bound to produce such imperfections as are found in the Speculum. Coster’s type were cast in one tempo, that is, the character itself and the shank cast at the same time in one piece.
Gutenberg’s patrices, according to Enschede, were made like bookbinders’ stamps, of yellow copper, i. e., brass. With such patrices only lead matrices could be made, but the latter could be produced in two ways. Molten lead could be poured over the patrices or the patrices could be pressed into cold lead. The first mode is somewhat complex, but the matrix would have a smooth surface and need no further adjustment.