540 



HISTORY OP THE VEGETABLE KINGDOM. 



colour, and abounding in a milky juice. Tlie 

 stalks are numerous, shrubby, slender, striated. 



208. 



Jalap. 



twisted, and climb for support to other bodies, 

 rising to twelve feet in height. The leaves vary 

 in form, but are generally heart-shaped; they 

 are smooth, of a bright green colour, and stand 

 alternately upon long footstalks. The flowers 

 are large, bell-shaped, entire, and plicated, of a 

 reddish colour externally, but a purple within. 

 The flowers appear in August and September. 

 It is said that the root of Jalap was first brought 

 to Europe about the year 1610. It is now one 

 of the most common purgatives. The root has 

 little smell or taste, but imparts a slight degree 

 of pungency in the mouth. Its medicinal activity 

 resides in the resinous matter of the root. It is 

 found to be a safe and efficacious purgative, when 

 given in doses of twenty to thirty grains of the 

 powdered root. The root requires to be well 

 pounded, so as to separate the resinous particles, 

 and for this purpose crystals of tartrate of potass 

 are often added. 



It may also be dissolved in proof spirits, and 

 administered in tincture, either alone or conjoined 

 with senna or aloes. 



Buckthorn (rhamnus catharticus.) Natural 

 family, rhamni ; pentandria, monogyiiia, of Lin- 

 niEus. This shmb is a native of Britain, and 

 usually is to be found in woods and hedges near 

 running streams. The stem is covered with 

 dark brown bark, and divides into many branches 

 beset with strong spines. Its height is seven or 

 eight feet. The leaves are elliptical, serrated, 

 and stand on short footstalks. The flowers are 

 commonly male and female on different plants. 

 Ther-e is no corolla ; the calyx is of a greenish 

 yellow colour, divided at the extremity into 

 four segments. The fruit is a round black berry, 

 containing four seeds. It flowers iu May or 

 June, and the seeds are ripe about the end of 

 September. 



The berries, which are the medicinal part of 

 the shrub, contain a pulpy deep green juice, 

 which has a faint unpleasant smell and a bitter 

 acrid taste. Twenty of the fresh berries produce 

 a purgative eifect, with heat and thirst, and often 

 severe griping. The expressed juice and powder 

 of the dried berries have also similar eff'ects. A 

 syrup is made of the expressed juice and sugar. 

 Though a powerful purgative, and useful in 

 dropsies and obstinate costiveness of habit, it is 

 now seldom used in modern practice, on account 

 of the violence of its effects. The inner bark 

 is also of a purgative nature. 



The juice of the unripe berries stains paper of 

 a saffron yellow. The juice of the ripe berries, 

 mixed with alum, forms the sap green of artists. 

 If the berries be allowed to get over ripe, their 

 juice produces a,purple colour ; the bark yields a 

 beautiful yellow dye. 



209. 



Senna (cassia Egyptiaca). Natural family, 

 hguminoscB ; dccandria, monogynia, of Linnaeus. 

 This plant is an annual; -the stalk is strong, 

 smooth, branched, and rises to the height of about 

 two feet. The leaves are alternate, with narrow 

 pointed stipulse at the base. Each leaf is com- 

 posed of several pairs of oval or elliptical pointed 

 nerved sessile pinnse, of a yellowish green colour. 

 The flowers are yellow, and produced succes- 

 sively in long axillary spikes. They appear in 

 July and August. The seeds are contained in a 

 compressed curved pod. This plant is a native 

 of Egj'pt, it also grows in some parts of Arabia, 

 especially about Mocha ; but as Alexandria has 

 ever been the great mart from which it has been 

 exported into Europe, it has long been known 

 under the name of Alexandria senna, or sena. 

 Hassilquist found this plant growing spontane- 

 ously in Upper Egypt. The blunt leaved senna, 

 (S". natica, is a variety of the sea species, which 

 by its cultivation in the south of France has been 



