LEGUMINOSjE. 401 



inspissation. It owes its sweetness to a peculiar principle called Glycion, 

 or Glycyrrhizin, which appears also to be present in the root and 

 leaves of other papilionaceous plants, as Glycyrrhiza echinata and 

 ylandulifera, Trifolium alpinum and Abrus precatorius. Liquorice is 

 used medicinally as a demulcent. A sweet secretion (a kind of Manna) 

 is produced by Alhagi Maurorum. Astragalus verus, creticus, aristatus, 

 gummifer, and other species, yield an exudation known by the name 

 of Gum Tragacanth. A. verus seems to be the chief source of the 

 European tragacanth. It is a shrub found in Asia Minor and Persia, 

 and the gum is procured by exudation or incision. Tragacanth forms 

 with cold water a bulky jelly, while it is soluble in boiling water. It 

 contains both Arabin and Bassorin in its composition, and is used as a 

 demulcent. Myrospermum, or Myroxylonperuiferum, yields the Balsam 

 of Peru, while Myrospermum, or Myroxylon toluiferum, is the source of 

 the Balsam of Tolu. These balsams are procured chiefly by making 

 incisions in the trees. They consist of resinous and oily matter, with 

 cinnamic acid, and they are used as stimulant expectorants. Pterocarpus 

 Marsupium, a tree of the Indian forests, furnishes the concrete exuda- 

 tion caUed Kino. Butea frondosa, or the Dhak tree of the East Indies, 

 yields a similar product, and African Kino is procured from Pterocarpus 

 erinaceus. Kino is used as a powerful astringent, and is administered 

 in the form of powder and tincture. Broom-tops, procured from 

 Cytisus (Sarothamnus) Scoparius, are used as a diuretic. The hairs from 

 the legumes of Mucuna pruriens in the West Indies, and of M. prurita 

 in the East, under the name of Cowhage, or Cowitch, have irritat- 

 ing properties, and, mixed with syrup, they are used in the treat- 

 ment of intestinal worms. The leaves of Colutea arborescens, Bladder- 

 Senna (fig. 470), are purgative, and are used abroad to adulterate the 

 obovate or blunt-pointed Senna. The leaves of Tephrosia apollinea 

 are also purgative, and are occasionally mixed with Alexandrian 

 Senna. The bark of Andira inermis, the Cabbage-tree of the West 

 Indies, acts as a purgative and anthelmintic. The fruit of Geoffroya 

 superba, Umari, is much used by the inhabitants of Brazil on the 

 banks of the Rio San Francisco ; the fruit is a drupe. 



Besides the plants which have active medicinal qualities, there are 

 others which are valuable in commerce and the arts, as furnishing 

 food, dyes, fibres, timber. Various species of Indigofera, as /. tinctoria 

 and ccerulea, furnish the Indigo of commerce. Pterocarpus santalinus 

 yields red Sandal- wood, which is used as a dye. P. Draco yields 

 Gum-Dragon, and P. Dalbergioides is said to yield Andaman redwood, 

 and to be valuable both as a dye and as timber. Saptisia tinctoria 

 gives a blue dye, and is the Wild Indigo of the United States. Dal- 

 bergia Sissoo is an Indian forest tree, which is valued on account of its 

 wood. Crotalaria juncea supplies fibres, which are known as Sun or 

 Bengal Hemp. The fragrant seeds of Dipterix odorata are known as 



2D 



