ENGRAVING IN AQUA TINTA. 455 



with the pencil, and mixed with lamp-black to give 

 it colour ; for if transparent, the touches of the 

 pencil would not be so distinctly seen. The mar- 

 gin of the plate must also be covered with varnish. 

 When the stopping out is sufficiently dry, a border 

 of wax must be raised round the plate, in the same 

 manner as in etching, and the aqua fortis properly 

 diluted with water poured on. This is called biting 

 in, and is the part of the process which is most 

 uncertain, and which requires the greatest degree 

 of experience. When the aqua fortis has lain on 

 so long that the plate, when printed would produce 

 the lightest tint in the drawing, it is poured off, 

 and the plate washed with water, and dried. When 

 it is quite dry, the lightest tints in the drawing are 

 stopped out, and the aqua fortis poured on as be- 

 fore, and the same process is repeated as often as 

 there are tints to be produced in the plate. 



Although many plates are etched entirely by this 

 method of stopping out and biting in alternately, 

 yet it may easily be conceived, that in general, it 

 would be very difficult to stop round, and leave out 

 all the finishing touches, as also the leaves of trees 

 and many other objects, which it would be impos- 

 sible to execute with the necessary degree of free- 

 dom, in this manner. 



To overcome this difficulty, another very ingeni- 

 ous process has been invented, by which these 

 touches are laid on the plate with the same ease and 

 expedition as they are in a drawing in Indian-ink. 

 Fine washed whiting is mixed with a little treacle 

 or sugar, and diluted with water in the pencil, so 

 as to work freely, and this is laid on the plate 

 covered with the aqua-tint ground, in the same 

 manner, and on the same parts as ink on the draw- 

 ing. When this is dry, the whole plate is varnished 



