656 



HISTORY OP THE VEGETABLE KINGDOM. 



Dandelion (leontodon taraxacum J. Natural 

 family compositce; st/ngencsia, polygamia equalis, 

 of Linnseus. This is perhaps one of the com- 

 monest weeds, the small seed being furnished 

 with a downy appendage, which readily carries 

 it along upon the wind, and diffuses it in all 

 waste places. The leaves are radical and deeply 

 indented, in such a way as has been termed 

 runcinata. The flower stalk is simple, fistulous, 

 coloured of a pinkish hue, and bears one flower. 

 The outer calyces are bent downwards. The 

 seeds, which are numerous, are crowned with a 

 fine downy feather, and are disposed in a spher- 

 ical shape. 



The young leaves, in a blanched state, have 

 the taste of endive, and are frequently used in 

 spring, mixed with other salad plants. In Ger- 

 many, the roots are roasted and substituted for 

 coffee by the poorer inhabitants, who say that 

 an infusion prepared in this way, can hardly be 

 distinguished from that of real coffee. This 

 plant yields a milky juice similar to that of the 

 lettuce and others. It is bitter, and somewhat 

 acrid; but the juice of the root is still more 

 powerful. It has been found a general stimu- 

 lant to the system, but especially to the urinary 

 organs. Some of the older physicians recom- 

 mend it in obstructions of the liver, and hypo- 

 chondriacal diseases. In modern practice, how- 

 ever, it is superseded by more active medicines, 

 of a similar tendency. 



Yarrow, or Millfoil. Natural family com- 

 positw; syngenesia, polygamia superflua, of Lin- 

 nseus. This is a common perennial plant, found 

 in dry pastures on the steep banks of rivers, in 

 Britain. The stalk is smooth and downy, and 

 grows to the height of ten or twelve inches. The 

 leaves stand alternately on the stem, which they 

 partly embrace, and are subdivided into a double 

 series of pinna;; they are numerous, narrow, and 

 somewhat pointed. Theflowers are small, white, 

 or purplish, and terminate the stem in a close 

 corymb. Both the flowers and leaves have an 

 aromatic, rather agreeable smell, and a bitter, 

 rough, and somewhat pungent taste. 



Both water and proof spirit extract the virtue 

 of this plant; and by distillation it yields a pene- 

 trating, essential oil, possessing the peculiar 

 flavour of the plant in perfection. 



The millfoil was known to the ancient physi- 

 cians, and was esteemed by them as a cure for 

 wounds and bleeding vessels; but tlie modem 

 art of surgery has now dispensed with all such 

 applications. 



Internally, it has been used in Germany as a 

 tonic, antispasmodic, and sedative. That it pos- 

 sesses some narcotic qualities, would appear from 

 the fact in Sweden, that it is used in making beer, 

 to wliich it imparts an additional intoxicating 

 quality. In modern practice, it is never used 

 as a medicine. 



CHAP. LI. 



OUMS, RESINS, AND BALSAMS. 



In a former part of this work,* we described 

 generally the various vegetable products obtained 

 from plants; and, amongst othere, the gums, 

 resins, and balsams. We shall now more par- 

 ticularly describe the trees and plants from which 

 those substances, as for as known, are obtained. 



By gum or mucilage, is understood a substance 

 soluble in water, but insoluble in alcohol. Resins 

 are, on the contrary, soluble in alcohol and the 

 essential oils, but insoluble in water. Gum 

 resins are substances composed both of resin and 

 gum, or mucilage; and balsams are combinations 

 of one or both of these, with benzoic acid. 



Gum Arabic Tree, or Egvptian Thorn (aca- 

 cia vera). Natural family leguminosce ; poly- 



220. 



Gum Arabic Tree. 



gamia, monoecia, of Linnseus. This is a stunted, 

 hard, withered looking tree, with a crooked stem, 

 covered with smooth, gray coloured bark. The 

 leaves are bipinnated, and placed alteraately; 

 the partial pinnte are opposite, furnished with a 

 small gland between the outermost pair, and 

 beset with numerous pairs of narrow, elliptical 

 leaflets. The spines are long, white, spreading, 

 and proceed from each side of the base of the 

 leaves. The flowers are hennaphrodite and 

 male; they assume a globular shape, and stand 

 four or five together upon slender peduncles, 

 which arise from the axilla; of the leaves. The 

 calyx is small, and the corolla consists of five 

 small, narrow segments, of a yellowish colour. 

 The fruit is a long pod, resembling that of the 

 lupine, and contains many flat, brown seeds. It 

 is a native of Arabia, and found in almost every 

 part of Africa. It flowers in July. This and 

 all the other species of the same family, are 

 easily cultivated in our green-houses. The first 

 plant of acacia, cultivated in England, was by 

 Evelyn, in 1G64. 



This tree appears to have been well known to 

 the ancients. Dioscorides not only mentions the 



* Cluap. xxU . _, 



