Ink., 
455 
ness) and suspended by means of glue* Their best glue 
was made by boiling bulls ears in vinegar and water. 
China or Indian ink, can be washed off the paper by 
the patient application of a brush and warm water* 
Hence, Mr. Sheldrake has proposed a mixture of turpen- 
tine varnish thinned by oil of turpentine and coloured by 
lamp black. Or better by dissolving gum- copal in oil of 
lavender, and rubbing it off with a small quantity of 
la mp black. I have repeatedly dissolved gum- copal by 
means of gentle heat and much patience, in oil of tur- 
pentine, and oil of rosemary, and still more easily in oil 
of pennyroyal and oil of burgamot, and so me other of 
the essential oils. This recine may answer for some cu- 
rious purpose, but it is not calculated for common use. 
Red ink is made with cochineal and gum arabic dis® 
solved in vinegar and water. Or by brazil, braziletto 
or nicaragua wood in the proportion of one ounce and 
a half to a pint of water, containing a quarter of an ounce 
of alum and half an ounce of gum arabic. Blue ink. 
Indigo and gum arabic. Grejen ink, dissolve in vinegar 
and water, crystallized verdigrease till the colour be suff 
fieiently strong ; thicken with gum arabic. Yellow ink ; 
is made either by a decoction of saffron, or of French 
berries (grains d* Avignon.) 
The common marking ink used for these thirty y ears in 
Manchester to mark the corners of the unbleached goods, 
is a solution of silver in nitrous acid, which when fused by 
fire, is the lunar caustic of the shops. Take of this one 
drachm, dissolve it in 4 times its weight of rain water : 
thicken it by putting in about half a drachm of gum arabic. 
Moisten the part you mean to mark, with a solution of one 
drachm of pearl ash in about six times as much water ; dry 
it, and then write with the ink. This ink is used by the 
dyers and printers of cotton goods previous to bleaching, 
because neither acids or alkalies discharge the stain. But 
