IMPROTEMENT IN THE AQUATINTA PROCESS. 2£3 



ground that will drain from the plate, and in the course of 

 a quarter of an hour the spirit will evaj)orate, 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 de- 

 sign 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 drkw 

 with to be made with a sharp point; if you intend to repre- 

 sent chalk-drawing, a very soft nib and broad-made pen wili 

 be necessary, or a small reed. 



No. 2. — Composition, resembling ink, to draw the design 

 on the copper. 



Take about one ou'oce of treacle or sugar candy, add to i;ik fordrair. 

 this three burnt corks reduced by the fire to almost an '"go" it- 

 impalpable 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 toward 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- Vamiih. 

 position, you will dry it at the fire until it becomes hard: 

 then varnish the plate all over with turpentine varnishf . 



It will now be necessary to let the varnish that is passed over 

 the plate, dry, which will take three or four hours at least; 



• Gum water must be made in the proportion of half an ounce of gum 

 sirabie to a quarter of a pint of water. 



f Turpentine varnish is composed of an ounce of black resin to an 

 eighth part of a pint of spirit of turpentine ; if the weather is excessively 

 warm, it ought to be made with a sixth part of a pint of spirit of turpeti- 

 tine. 



[I apprehend there is a mistake here, and that the proportions of spirit 

 should be reverted ; as more of the liquid would, no doubt, be required 

 in cold weath«r than in hot. C] 



bat 



