ON MADDER. 
133 
produce that well,) not gummed as usual, and dried. As 
many decimetres are cut from it as there are garancines to 
to be tried, and the pieces are marked by notching them 
with the scissors: the notches must correspond with the 
numbers on the bottles. 
From 1.9 grm. to 2 grms. of garancine, known to be good, 
is weighed otf to serve as standard, and for the garancines to 
be tried, we take 1, 2, 3, 4, 5, 6, 7, 8, 10 times more or less 
of 1.90 or 2 grammes, according as they cost 1, 2, 3, 4, &c. 
more or less than the standard sample. As the samples are 
weighed, they are each put into a jug with a wide mouth 
holding half a litre, with from 2 to 2\ decilitres of water 
containing some oxalic acid, in the proportion of 15 
centigrms. to a litre. The jugs are numbered so as to corres- 
pond with the samples of the garancines and strips of calico. 
They are placed in a water-bath, in a copper boiler with a 
flat bottom, the pieces of printed calico are immersed in 
them, and dyed as in testing the madders, regulating the fire 
so as to raise the temperature to 15S°in an hour and a half, 
and keeping it at the boiling-point for half an hour. After 
the process of dyeing, the samples are removed as quickly as 
possible from the vessels, rinsed in water and beaten, and 
then dried or previously immersed for five or six minutes 
in a bran-bath at 167°. When dry they are compared, and 
in this manner the relative tinctorial value of the garancines 
may be estimated as nearly as possible. 
In employing calicoes, which present at the same time 
stripes mordanted for red, violet, puce and garnet, it is seen 
at once whether the garancines can be employed with ad- 
vantage for all the colors, or for what tints they are most 
suited. I have already stated that the same garancine does 
not always suit equally well for red, puce and violet. 
Lond. Chem. Gaz. from Journ. de Pharm* 
12* 
