42 



versed. An instrument is now used called the etching 

 needle, to score the lines through the wax and lay bare 

 the surface of the copper. The pressure used is just 

 sufficient to remove the etching ground and slightly 

 scratch the surface of the metal beneath. The artist 

 works stroke by stroke, much the same as when drawing 

 with a pen, only in this case every mark shows white on 

 a black ground, just the reverse of pen drawing, and the 

 deepest shades show as patches of white. After the draw- 

 ing is completed the back of the plate is covered with a 

 varnish and immersed in a bath composed of equal parts 

 of nitric acid and water, the copper is attacked in those 

 parts laid bare by the etching needle, and after a sufficient 

 depth of line is obtained for the lightest parts, those 

 portions are stopped out with varnish, and the plate is 

 ajrain bitten until the darkest shades are obtained. 



To print well from copper or steel plates requires 

 great care. The press used consists of two great rollers, 

 between which travels a solid flat plate, called the bed, 

 on which rests the plate. The copper-plate is first heated 

 until it is as hot as the hand can bear, then it is inked all 

 over with a clabber and some force is used to drive the ink 

 well into the lines ; next the whole of the superfluous 

 ink is removed with a coarse muslin rag, and the palm of 

 the hand, and the copper margin of the plate cleansed 

 very carefully with whitening ; having marked the place of 

 the plate on a sheet of zinc, the printer lays it on the 

 zinc in its measured place, and over it spreads a sheet of 

 damp paper ; over this he places a number of thicknesses 

 of cloth, and the whole is forced between the rollers of 

 the press ; the pressure forces the paper into the lines of 

 the engraving, and, removing the ink, produces the pic- 

 ture. Usually the first hundred impressions of a choice 

 engraving are printed upon india paper, and are some- 



