MEMOIR OF THOMAS BEWICK. 
19 
which are sunk by the graver on the surface of a 
copper-plate are the parts which receive the printing 
ink, which is first smeared over the whole plate, and 
the superfluous ink is scraped and rubbed off, that re- 
maining in the lines being thus transferred upon the 
paper, by its being passed, together with the plate, 
through a rolling-press, the rest being left white — 
in the wooden block, all the parts which are intend- 
ed to leave the paper wdiite, are carefully scooped 
out with burins and gouges, and the lines and other 
parts of the surface of the block which are left pro- 
minent, after being inked, like types, with a ball or 
roller, are transferred to the paper by the common 
printing-press. The difficulty, therefore, of picking 
out, upon the wooden block, the minute squares or 
lozenges, which are formed by the mere intersection 
of the lines cut in the copper-plate, may easily be 
conceived. 
The great advantage of wood-engraving is, that 
the thickness of the blocks (which are generally of 
boxwood, sawed across the grain) being carefully 
regulated by the height of the types with which 
they are to be used, are set up in the same page 
with the types ; aud only one operation is required 
to print the letter press and the cut which is to il- 
lustrate it. The greater permanency, and indeed 
