150 
The Way Out For Indian Planters. 
How is the German move to be met ? There is a way out. It 
will be found in improved cultivation, on scientific principles, of 
the plant, and m improved methods of extracting the natural dye 
from the indigo plant. Considerable initiative and some outlay of 
capital is required. The old mechanical method of hand-and-foot 
labour as handed down from generation to generation, without any 
thought of improvement, will have to go. The process of extract- 
ing the maximum quantity of pure indigotine from the vats is being 
closely inquired into by experts, I am told. Authorities in che- 
mistry will undoubtedly succeed in obtaining increased proportions 
ot colouring matter from (he plant, which has hitherto not been 
expected to give more than i£ lbs. of indigo for ioo lbs. of the 
plant. At the present moment experiments are in progress in Cam- 
bodia which will be of particular interest to indigo planters in 
British India. I am told that one Martinique planter has succeeded 
in o aining a product containing 73 per cent, of pure indigotine 
^rr t ?4 I V^P erlb * This is at a notably lower cost than 
that ot artificial indigo, as stated above. 
It is thus far from a certainty that natural indigo will disappear 
from the market as soon as madder did when threatened by German 
chemical competition Indigo planters willing to radically alter 
their old-time methods, improve their cultivation of the crops and 
alter the mode of extraction of the dye, and who, by means of com- 
( ' na ? on VVI ^' °fhc]al help, can, make the necessary sacrifice that 
the changes will entail may take heart of grace. The last word 
has not been said yet on the subject of natural indigo. 
Dr. Calmette’s Method of Extraction. 
a, Lille, has patented the following process for 
the extraction of indigotine from the plant. Hitherto the leaves of 
the indigo plant have been placed in masonry vats in layers The 
vats are then filled to two-thirds with water, care being taken not 
to crush the leaves. The leaves are held down by planks, and 
water is let in to cover them. Fermentation then sets in and the 
hqmd, first yellow becomes by degress green. The temperature 
ot the vat rises, and soon the surface of the vat is covered by a film 
having a metalic scheen. In this operation f( indican ” the sub- 
stance contained in the plant, transforms itself into glucose and 
white mdigo under the influence of the fermentation caused by a 
bacillus living on the leaf of the indigo plant. The white indigo is 
transformed into blue mdigo by simply beating up the liquid bring- 
ing it into contact with air. H & 
u^K e ^°j tof '"c ig0 flak< ; s . is formed at the bottom of the vats. 
is one up with water, dried, and made into small cakes. The 
primitive method gave only about a third of the indigo contained 
m the plant. There is a considerable loss owing to the fermenta- 
ion. r. ALMETTE has endeavoured to regulate this fermentation; 
he suppresses it entirely and treats the leaf in close vats at a tem- 
pera ure o tty to sixty degress centigrade, unexposed to the 
oxygen of the air. The extraction of the “ indican ” and its trans- 
