THE BOX. 79 



She close of the seventeenth century, when the custom 

 of illustrating books with copper-plate engravings camo 

 into vogue, and wood-engraving was entirely neglected, so 

 far as it regarded the delineation of subjects of interest, 

 being employed solely for common decoration. That this 

 should have happened is remarkable, inasmuch as the 

 superiority of wooden blocks over copper plates in illustrat- 

 ing printed books is very great. In copper-plate engraving, 

 the lines from which the design is transferred are sunk 

 into the metal, either by the corroding effects of a mineral 

 acid, or by a sharp-pointed steel instrument. Conse- 

 quently the sunken lines must be filled with ink before 

 an impression can be struck off ; but in ordinary letter- 

 press printing, a raised surface alone receives the ink and 

 transfers the copy. Hence arises an impossibility of print- 

 ing both by the same process. But in wood-engraving, the 

 thickness of the wood being carefully regulated by the 

 height of the type with which it is to be used, the block 

 is set up in the same page with the types ; and only .one 

 impression is required to print the letter-press and the cut 

 which is to illustrate it. Added to this, the friction 

 (though produced simply by the soft fleshy ball of the 

 thumb) which is required to charge the lines of a copper- 

 plate engraving with ink, soon wears away the sharpness 

 of the lines, and renders every new impression less perfect 

 than its predecessor. But in printing woodcuts, the whole 

 of the pressure being vertical, there is no perceptible 

 wearing away of the block, so that the goodness of the 

 impression depends only on the materials employed, and 

 the care of the printer. 1 But even on the supposition that 

 the mechanical advantages of each were equal, the prefer- 

 ence must be awarded to woodcuts for the illustration of 



1 In an interesting Memoir of Bewick, prefixed to the sixth volume 

 of Jardine's "Naturalist's Library," it i-< stated that "many of 

 Bewick's blocks have printed upwards of 300,000 ; the head-piece 

 of the Newcastle Courant above 1,000,000 ; and a small vignette 

 for a capital letter in the Newcastle Chronicle, during a period of 

 twenty years, at least 2,000,000." 



