INDIGO. 



365 



during a few hours only, when they darken considerably, are put into 

 straw bags and kept for the purpose of afterwards undergoing a 

 longer treatment. This consists in moistening the leaves with a 

 certain amount of water, the exact quantity of which depends on the 

 natiu"e of the leaves, and the greatest care must be taken to prevent 

 its being either in excess or in deficiency. They are then spread out 

 upon and covered with mats during a few days, after which the opera- 

 tion is repeated during a period of eighty days, about twenty-five times 

 for the best, and about nine times for the inferior leaves. Having 

 undergone this kind of fermentation, they are then pounded in wooden 

 mortars, and in quantities of about 30 lbs., for two consecutive days, 

 so as to become reduced to a sort of paste, which is then formed into 

 balls of a dark blue colour. These balls of crude indigo, with an 

 addition of bran and potash lye, prepared from wood-ashes, form the 

 material used by dyers in the steeping vat. 



Java. — Indigo is grown principally in the middle provinces, where 

 there are some eighty plantations. In 1863 the exports were 

 915,000 lbs. In 1870 the shipments were 587,882 Amsterdam 

 pounds, and 510 piculs. Holland exports annually about 1,500,000 

 kilos,, obtained from its possessions in the East. 



Mr. Joseph Sayers, of Java, has carried out some improvements in 

 the manufacture of indigo, which are remarkable for the increase of 

 indigotine obtained, and the uniform results shown. These are stated 

 in the following comparative analyses of various kinds of commercial 

 indigo, as published by Mr. Henri Berge, chemist to the city of 

 Brussels, and professor of chemistry at the university of the same 

 town. It shows the sources, marks, and prices of some, in cents. 



Kind of Indigo and Marks 



Indlgotine, 



Ind 



go of Java, SK, at 75 Cent. 



ABCD, at 125 „ 



KP, at 225 „ 



„ GWG, at 460 „ 



WJF, at 550 „ 



CFE, at 600 „ 



of Bengal, at 450 „ 



„ at 525 „ 



of Manilla at 60 „ 



at 125 „ 



of Sayers of Java, No. 1 . . 



No. 2 .. 



No. 3 .. 



No. 4 .. 



„ No. 5 .. 



No. 6 .. 



No. 7 .. 



No. 8 .. 



No. 9 .. 



No. 10 .. 



No. 11 .. 



No. 12 .. 



No. 13 .. 



No. 24 ,. 



57-19 



14-28 



27-28 



44-47 



55-13 



9-02 



68-68 



5-09 



69-82 



2-18 



75-78 



2-69 



72-17 



2-93 



75-36 



1-99 



14-47 



45-63 



24-55 



37-98 



69-37 



2-31 



72-35 



2-82 



74-03 



2-59 



69-32 



3-48 



66-98 



4-25 



65-38 



3-95 



69-63 



2-89 



71-20 



1-53 



71-40 



2-36 



74-53 



1-61 



71-11 



2-14 



67-89 



2-76 



67-85 



2-66 



76-70 



2-50 



