"unmixed lead," with which he printed five hundred impressions on rough and dry paper. He says that the types showed no appreciable wear; but this is not surprising, for we have evidences that they were printed by an expert pressman on an iron press provided with every appliance requisite for a nice adjustment of the impression.
It is not at all probable that the press of the unknown printer had these handy appliances. All the printing presses made before the nineteenth century had wooden frames, with beds of slate or stone, and platens or pressing surfaces of wood. Impression was given by the direct action of a screw, the force applied being regulated only by the discretion of the pressman. Knight, in his essay on Caxton, says the press of that printer was a modification of the cheese-press, provided with an attachment that permitted the form of types to be moved in and out of the press. German authors say that the first printing press was a modification of the wine-press. Bernard says it was, probably, an improved form of coining or stamping press. But these are only conjectures. We can find no engraving nor any verbal description of the form of the printing press in use during the fifteenth century. The general neglect by all artists and writers of this important auxiliary to printing is an indication that no importance was attached either to the mechanism of the press or to the principle of impression. It seems to have been generally understood that, whatever merit there might have been in the invention of printing, no noteworthy inventive skill had been shown in the construction of the press. It was not only a rude but an old contrivance.
We have many evidences that the press of the unknown printer was of the rudest construction. Some pages have the marks of strong pressure in one corner and of weak impression in another—manifestly the result of the printer's inability to regulate or control the force he exerted. The margins of the Speculum are of unequal width; the type-work is rarely ever parallel with the engraving at the head or at a proper