406 LEGUMINOSZ. 
into two cells, each of which contains a single row of small 
greyish-yellow rhomboidal seeds, deeply notched on one side, 
and seen under the microscope to be marked with numerous 
black spots. The other kind with very small slightly curved — 
pods mentioned by Mahometan writers is not found in the 
shops. 
Chemical composition.—Coumarin, C9 H® 02, the anhydride — 
of coumaricacid, C? H® 0%, and the odorous principle of melilot, 
is found in several plants ; it is best prepared from the Tonka 
bean, Cowmarouna odorata, by digesting in strong alcohol, 
on evaporating, a crystalline magma is obtained, which when — 
purified with animal charcoal is colourless; it crystallizes in 
trichlinic crystals; melts at 50° C., and boils at 270° without 
sensible alteration; it has an agreeable aromatic odour, and a 
bitterish burning taste, the vapour acts strongly upon the 
brain; coumarin is nearly insoluble in cold water, boiling 
* water dissolves it freely, and deposits it on cooling in slender 
needles, It dissolves without alteration in dilute acids, 
Commerce.—Iklil-el-malik is sold for six annas per lb. 
INDIGOFERA TINCTORIA, Linn. 
Fig.—Rheede, Hort. Mal. ¢., t.54; Wight Ic. t. 365, Dyer’s 
Indigo (Hng.), Indigotier tinctorial (Fr.), 
Hab.—Western India, cultivated elsewhere. The plant 
and Indigo. 
Vernacular.—Nil (Hind., Beng.), Nili (Mar., Can.), Nilam 
(Tam.), Nili-mandu (Tel.), Gali (Guz.). 
History, Uses, &c.—Indigo, in Sanskrit Nila, a word — 
which signifies dark blue or black, appears to have been known 
in the Hast as a dye and medicine from a very remote period. 
Its importance as an article of trade is indicated by the Sans- 
krit synonym Banigbandhu, or “ trader’s friend.” It was 
probably exported from Cambay, Broach and Thana ata very _ 
early period, certainly from the latter port B. C. 80. What e 
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