132 
ON MADDER. 
obliging him to brighten the tint of his powders, in order to 
make them more saleable, and that sometimes to the injury 
of the tinctorial power ; thus facilitating the adulteration of 
the madders by mixture with foreign substances, suitably 
colored and pulverized, which serve to heighten the tint of 
the powder; and it is impossible to ascertain the presence 
of these mixtures by exposure in the cellar, of which I have 
often had proofs. I have purposely made mixtures of mad- 
der, of powders of mahogany and of sandal wood in known 
proportions, and these mixtures, when tried by the mer- 
chants, who thought themselves very skilful in their esti- 
mation of madders, by the above process, were considered 
by them to be pure madders of first quality ! 
Testing of the Garancines. — The quality of the garan- 
cines varies, as I have already stated, considerably. A 
manufacturer sometimes sends a scries of from fifteen to 
twenty barrels of excellent quality, and fifteen days later 
sends another series which is worth from 20 to 25 per cent, 
less than the preceding one. It often happens that in the 
same series good and bad garancine is found ; each barrel 
therefore of this product should be tested comparatively as 
far as possible. It is now customary for the seller to take back 
the garancines which he had delivered to the calico-printer, 
allowing for the pieces spoiled, when the quality of the pow- 
ders was inferior to what it was represented. 
The testing of garancines is made on a large and on a 
small scale. In the latter case the following is the process 
we adopt : — 
Samples are taken from the barrels as they arrive, taking 
eare to cork the labelled bottles in which they are inclosed 
as quickly as possible, in order that they may not dry, which 
in summer time especially causes an amelioration of from 
5 to 6 per cent, in a few days, on account of the water 
which evaporates. 
A piece of calico, printed in stripes of red, violet, puce 
and garnet* is taken (black is useless, as all the garancines 
