Improvements in the Aquatinta Process. 299 
spirits of wine, of the strength to fire gunpowder when the 
spirits are lighted. 
During the course of twenty-four hours this composition 
must be repeatedly shook, until the whole appears dissolved ; : 
then filter it through blotting-paper, and it will be fit to use. 
Tn pouring on this ground, an inclination must be given 
to the plate that the superfluous part of the composition’ 
may run off at the opposite side; then place a piece of 
blotting- paper along this extremity, that it may suck up the 
ground that will drain from the plate, and in the course of 
a quarter of an hour the spirit will evaporate, and leave a 
perfect ground that will cover the surface of the copper, 
hard and dry enough to proceed with. 
With an exceeding soft black-lead pencil sketch your 
design on this ground, and when finished take a pen and 
draw with the following composition, resembling ink: if 
you wish your outline to be thin and delicate, cause the pen 
you draw with to be made with a sharp point; if you in- 
tend to represent chalk-drawing, a very soft nib and broad 
made pen will be necessary, or a small reed. 
No. 2.—Composition, resembling ink, to draw the de- 
sign on the copper. 
Take about one ounce of treacle or sugar-candy, add to 
this three burnt corks reduced by the fire to almost an im- 
palpable powder, then add a small quantity of lamp-black 
to colour it; to these put some weak gum-water, (made of 
gum-arabic,) and grind the whole together on a stone with 
a muller: keep reducing this ink with gum-water until it 
flows with ease from the pen or reed. 
To make the ink discharge freely from the pen, it must 
be scraped rather thin towards the end of the nib, on the 
back part of the quill, and if the liquid is thick reduce it 
with hot water. . 
Having made the drawing on the copper with this com- 
position, you will dry it at the fire anti! it becomes hard; 
then yarnish the plate all over with turpentine-varnish 
(No. 3,) of the consistency of the liquid varnish sent with 
this as a sample. : 
Ii will now be necessary to let the varnish, that is passed 
over the plate, dry, which will take three or four hours at 
Jeast; but this will depend on the state of the weather; for 
if it should be intensely hot, it ought to be left all night to 
harden. 
Now the varnish is presumed to be sufficiently hard, you 
may rub off the touches made with the foregoing described 
junk with spittle, and use your finger to rub them up; should 
It 
