ENGRAVING. 



appears, the plate must be placed horizontally, 

 when the spirit will evaporate, and the particles 

 of rosin will adhere to the copper. When dry, 

 the surface appears evenly covered, as with a 

 diminutive honeycomb, and perfectly smooth. 

 On this the subject is traced, and the highest 

 lights painted out with a sable pencil in a mixture 

 of turpentine varnish and lampblack, so as to 

 prevent the aquafortis acting on those parts. The 

 margin is also covered, and on it a wall of wax is 

 fixed, with a spout at one corner. The aquafortis 

 is regulated in its strength by the temperature 

 of the weather and the hardness of the copper. 

 Being poured on the plate, it remains until the 

 first gradation of tint is bitten the aquafortis 

 having acted on the copper between the particles 

 of rosin which adhered to the plate. The aqua- 

 fortis is then taken off, the plate dried, and this 

 first degree of tint stopped out or covered over 

 with the blackened varnish. When hard, the 

 aquafortis is again poured on, to bite the second 

 degree of tint ; and so on until all the tints have 

 in succession been bitten in. The copper must 

 then be cleaned, and a proof taken and compared 

 with the original. A similar or rebiting grain 

 must then be laid on the plate as before ; when 

 cold, a composition of treacle and lampblack, 

 well mixed, must be used to paint the projections 

 of foliage on lights, or other touches which the 

 masses of tint may require. When these are dry, 

 the whole of the plate must be washed over with 

 a thin coat of varnish reduced with turpentine, 

 which will adhere to the untouched parts of the 

 work. The wall of wax must then be replaced, 

 and clean water poured on ; in a short time the 

 water will mix with the treacle-touches, and loosen 

 them. When all appear to be removed, the water 

 is taken off, and aquafortis poured on, and allowed 

 to remain until a sufficient degree of power is 

 given to the touches, and the subject completed. 

 This mode of engraving was invented by a 

 Frenchman of the name of St Non, about the 

 year 1662. He communicated the process to 

 Jean Baptiste le Prince, who died in 1781, from 

 whom it was acquired by Paul Sandby, who intro- 

 duced it, through the medium of Mr Jukes, into 

 this country. It has been practised in England 

 with much greater success than anywhere else, 

 but latterly has been superseded in many instances 

 by lithography. 



Plate-printing. Copper-plates, engraved in any 

 of the above styles, are ready for press as soon as 

 they are finished by the engraver. The method 

 of printing from them is very simple. Their 

 engraved surface is daubed over with a thick 

 oleaginous ink, so that the lines are effectually 

 filled. As this dirties the whole face of the plate, 

 it is necessary to clean it, which is done by the 

 workman wiping it first with a piece of cloth, and 

 then with the palms of his hands, rubbed on fine 

 whiting. It may be calculated that a hundred 

 times more ink is thus removed than actually 

 remains in the indentations; however, such is 

 necessary. The plate being thoroughly cleaned, 

 it is laid on a press (see fig. 10), with a piece of 

 damped paper over it, and being wound beneath 

 a roller covered with blanket-stuff, it is forced to 

 yield an impression on the paper. The plate 

 requires to be kept at a moderate warmth during 

 the operation. The frequent rubbing of the plate 

 with the hand to clean it, as may be supposed, 



tends greatly to wear it down ; and such is the 

 wear chiefly from this cause, that few copper-plates 



Fig. 10. 



will yield more than a few thousands of impres- 

 sions in good order. The earliest, called proofs, 

 are always the best, and most highly prized. 



In consequence of this defect in copper, all sub- 

 jects requiring a great many impressions are now 

 engraved on steel-plates. This process was intro- 

 duced by the late Mr Perkins of London, who 

 originally softened the plates, engraved them, and 

 then rehardened them a practice now abandoned, 

 as ordinary steel-plates can be worked upon by 

 the burin, dry point, scraper, and burnisher with 

 perfect facility. Etching on steel-plates is executed 

 much in the same way as in the process on copper. 

 The plate is bedded on common glaziers' putty, 

 and a ground of Brunswick black is laid on in the 

 usual way, through which the needle scratches. 

 The biting menstruum is then poured on, and 

 managed in the manner already detailed. An 

 engraving on a steel-plate may be transferred in 

 relief to a softened steel cylinder by pressure ; and 

 this cylinder, after being hardened, may again 

 transfer the design by rolling it upon a fresh steel- 

 plate ; and thus the design may be multiplied at 

 pleasure. 



It is very much to be regretted that this beau- 

 tiful art is gradually declining. Although many 

 able engravers still practise it successfully, the 

 demand is so restricted, that very few pupils are 

 being trained to follow in their footsteps. The 

 necessarily great cost of good work, and the great 

 advance of wood-engraving, lithography, and pho- 

 tography are surely, if slowly, making it a thing of 

 the past 



SEAL AND GEM ENGRAVING. 



This is a branch of the profession altogether 

 distinct from that of engraving on metallic plates. 

 While the hardest metals are susceptible of being 

 cut by a tool wielded by the hand of the artist, 

 the different kinds of stone requiring to be oper- 

 ated upon by the seal-engraver are o extremely 

 hard, that a much more powerful instrument than 

 the hand has to be resorted to. The cutting-tool 

 is fixed into a turning-machine or lathe, and is 

 made to operate while in a rapid rotatory motion. 

 The lathe is of a light and miniature construction, 

 erected on an elevated bench or table in front of 

 the artist, and is moved by a footboard beneath. 

 The engraver of metal-plates sits while at his 

 work, but the seal-engraver in general stands, in 

 order to have greater command over his operations. 



