LEGUMINOSyE PRODUCING TANNING MATTERS AND DYES 337 



This is the case in India, but of recent years a start has 

 been made on reguhir plantations. 



All these data as to the variation in the yield and equality 

 are equally applicable to plants which produce dyes. A 

 special note is appended on each of the principal species. 



PAPILIONACE/E. 



Baphia laurifolia (Tree). — Both bark and wood contain tannin and 

 are used in dyeing. 



Baphia nitida (Shrub). — In cold water the wood yields a dye of a 

 fairly bright red. 



Baptisia tinctoria (Herb). — In U.S.A. this plant is used as a sub- 

 stitute for indigo. A blue colouring matter is extracted from the 

 leaves. 



Butea frondosa (Tree).-^This tree produces an astringent gum, and 

 the bark contains a large amount of tannin, but it does not appear 

 to be used in the preparation of leather. In the French possessions 

 in India the bark is used for dyeing blue and for tanning. The 

 flowers yield a yellow dye of good quality. Natives make use of the 

 gum in order to precipitate and purify indigo-blue. 



Clitoria Ternatea (Liane). — In Martinique the flowers are used for 

 obtaining a blue dye. 



Cylista scariosa (Herb). — The root of this plant is astringent and 

 contains about 10 per cent, of tannin. 



Dalbergia latifolia (Tree). — A decoction of the bark of this tree is 

 exported from Coorg (India) for tanning purposes. It is very 

 astringent. 



Desmodium sp. (Undershrub). — The leaves of this plant contain 

 blue colouring matter similar to that of the indigo-tree. After 



a 



S"- 



treatment with lime the natives use it to dye their stuffs. 



Flemmgia Crahamiana (Shrub).— Produces a red colouring matter of 

 considerable value. 



Endigofera tinctoria (Shrub). — The plants belonging to this genus 

 of Leguminosae yield the blue •colouring matter known as indigo. 



The chief species is IncLigofcra t'uictoria, a native of the East Indies. 

 The cultivation of the plant and the extraction of the colouring matter 

 vary in different countries, but the blue matter as it occurs in com- 

 merce does not exist by any means in the same form in the leaves. 



The leaves contain a colourless matter called indicmi. After fer- 

 mentation this matter is converted into iiidigotin, which is soluble, after 

 reduction, in an alkaline wash, and is then in the state of indigo white. 

 Vigorous churning of the liquids causes the indigo white to become 

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