No experiments sufficiently decisive have been made 
on the preference that ought to be given to cherry or 
plum-tree gum, gum tragacanth, gelatine of flour, com- 
mon glue, isinglass, or fish glue over gum arabic or gum 
Senegal. Lewis says that all the vegetable gums answer 
nearly the same purpose, but that the animal glues do not. 
Of this I am by no means persuaded. Sour ale and 
water, makes a very glossy ink. If China or Indian 
ink be dissolved in a large proportion of water, the black 
sediment appears to be lamp black or ivory black, and 
the liquor putrefying, indicates that the colouring mat- 
ter is suspended by animal jelly. 
The preceding recipe for writing ink, contains more 
galls than are necessary to the highest degree of blackness, 
but not more than are necessary to the durability of the 
ink. For present purposes, one third of the galls may 
be omitted. 
Common ink powder is thus made. Galls in powder 
two parts by weight ; green vitriol in powder one part ; 
gum arabic in powder one part ; sugar one fourth of a 
part. These should be dissolved in water and vinegar, of 
which the latter may be in the proportion of one third, 
to the water. 
A few cloves prevent the mouldiness of ink. I think 
cotton in an ink-bottle tends to preserve the colour. 
As the fugitive part of ink is the gallic acid, old writ- 
ings that have become illegible through time, may be 
rendered legible, by brushing them over with a solution 
of nutgalls in water ; or by a dilute solution of prussiat 
of potash. 
The colour of common ink is completely destroyed by 
Oxy muriatic acid. This effect is counteracted by rub- 
bing up some lamp black with the ink. 
The ink of the ancients, was of the same nature with 
China or Indian ink, being made of lampblack (probably 
calcined to improve the colour and diminish the greasi- 
