On the Art of Aquatint a Engraving. 1.35 



times various parts arc laid with different grains, according 

 to the nature of the subject. 



" The finer the grain is, ihe more nearly does the impres- 

 sion resemble Indian ink, and the filter it is for imitating 

 drawings. But very fine grains have several disadvantages : 

 for they are apt to come off before the aquafortis has lain 

 on long enough to produce the desired depth ; and as the 

 plate is not corroded so deep, it sooner wears out in print- 

 ing: whereas coarser grains are iirnier, the acid goes deeper, 

 and the plate will throw off a great many more impressions. 

 The reason of all this is evident, when it is considered, that 

 in the fine grains the particles are small and near to each 

 other, and consequently the aquafortis, v/Iiich acts laterally 

 as well as downwards, soon undermines the particles and 

 causes them to come off. If left too long on the plate, the 

 acid would eat away the grain entirely. 



" On these accounts, therefore, the moderately coarse 

 grains are more souiiht after, and answer better the pur- 

 pose of the publisher, than the fine grains whish were for- 

 merly in use. 



"Although there are considerable difficulties in laying pro- 

 perly the aquatint grain, yet the corroding the copper, or 

 biting in, so as to produce exactly the tint required, is still 

 more precarious and uncertain. All engravers allow that no 

 positive rules can be laid down by which the success of the 

 process can be secured; nothing but a great deal of expe- 

 rience and attentive observation can enable the artist to do 

 it with any degree of certainty. 



" There are some hints, however, which may be of con- 

 siderable importance to the person who wishes to attain the 

 practice of this art. 



*' It is evident, that the longer tbe acid remains on the 

 copper, the deeper it bites, and consequently the darker will 

 be tlie shade in the impression. It niav he of some use, 

 therefore, to have several bits of copper laid with aquatint 

 ground of the same kind that is to be used in the plate, and 

 to let the aquafortis remain for different lengths of time on 

 each ; and then to examine the tints produced in one, two, 

 iliree, four minutes, or longer. Obscryations of this kind 

 frequently repeated, and with different degrees of strength 

 of the acid, will at length assist the judgment in guessing 

 at the tint which is produetd in the plate. A magnifier is 

 also useful to examine the grain, and to observe the depth to 

 which it is bit. It must be observed that no proof of the 

 plate can be obtained till the whole process is finished. 

 " If any pan appears to have been bit loo dark, it musfc 

 I 4 be 



