and in Bihar 20 Ibs. per acre.* Indigo is ripe for cutting 

 when the flowers are just appearing, i.e. about June or July, if 

 sowing is done in February to April. The arrangements for 

 manufacturing being completed, cutting begins. The lowest 

 lying fields are chosen first. The crop is cut with sickles 

 and tied into bundles, and as the crop is bought at so many 

 bundles (say 4 or 5) per rupee, when it is cultivated by raiyats 

 and sold to the factory, a chain of a definite measure is used 

 in each factory. But different factories use chains of different 

 lengths. 



630. Manufacture. The bundles of plants are put in 

 fresh in the steeping vat, water is poured upon them and 

 they are pressed by means of bamboo rods and heavy beams 

 of timber. The bundles remain in this condition for one 

 night. There are two sets of vats. The second set is at a 

 lower level to the steeping vats and when steeping has been 

 completed in the first set, the yellowish liquid containing the 

 dye is drawn off from it into the second set. Here twice the 

 number of men employed in pressing the bundles is em- 

 ployed inside the vats in stirring up the liquid with bamboos 

 to oxygenate it. When the liquid has changed from a 

 yellowish colour to indigo colour the stirring is completed. 

 From these stirring vats the liquid is run off along a channel 

 into a trough or well, whence it is pumped up into the first 

 drying house, where it is subjected to boiling. From here 



With the help of Mr. Rawson's Blower for oxidising the liquid as it 

 comes from the steeping vat 25 to 30 per cent., more of colouring matter has 

 been obtained. With the ordinary appliances Bihar factors obtain about 

 10 seers of indigo (60 per cent, purity) out of every 100 maunds of green 

 plant, and with the blower 12^ seers are obtained. The indigotin is contained 

 in the leaf, and the weight of leaf on plants may be as much as 60 per cent., 

 or as little as 10 per cent. The leaf of Indigofera tinctoria of Bihar yields 

 about '55 per cent., of indigotin, which is equivalent to 36 seers of indigo 

 out of 106 maunds of leaf. Taking an average good plant to contain 40 per 

 cent., of leaf, 100 maunds of green plant would yield 147 seers of indigo (60 



