15S Preparation of Ox- Gall. 
with very little expense, which will be a great saving to 
those who use gall* as it will prevent it from putrifying, 
©r breeding maggots. 
One gall prepared in my method will serve an artist a 
long time^ as it will keep a great number of years. It 
will be a convenient article for use, as a small cup of it 
may be placed in the same box which contains other co- 
lours, where it will be always ready. The qualities of 
gall are well known to artists in water-colours, particu- 
larly to those who colour prints, as many colours will 
not, without gall, work free on such paper, on account of 
the oil that is used in the printing-ink. 
The artists who make drawings in water-colours also 
use gall in the water which they mix their colour with, as 
it clears away that greasiness, which arises from moist 
hands upon paper, and makes the colour work clear and 
bright. My preparation is ready for use in a few mi- 
nutes, all that is necessary being to dissolve about the 
size of a pea of it in a table-spoonful of water. 
It is also of great use to housekeepers, sailors, and 
others, to clean woollen clothes from grease, tar, &c. ; and 
will be found advantageous for many other purposes. 
If it should meet with the approbation of the Society, 
I have no objection to prepare it for sale. 
I am Sir, your obedient servant, 
RICHARD CATHERY, 
Botanical Coloured . 
Process for preparing Ox -Gall in a concentrated state , 
by Mr . Cathery . 
Take a gall fresh from the ox, and put it into a basin^ 
let it stand all night to settle, then pour it off from the 
sediment into a clean earthen mug, and set it in a sauce- 
pan of boiling water over the lire, taking care that none 
of the water gets into the mug. jLet it boil till it is quite 
