544 MEDICAL BOTANY. 



with those of R. undulatum, as being those of the true Rhubarb plant. 

 Pallas, however, states that he was informed by the Bucharian Rhubarb mer- 

 chants that they were unacquainted with leaves of a Rhubarb resembling this 

 species, and that those of the plant furnishing the commercial article were 

 round and much cut at the edges. The opinion of writers, however, still 

 leans to the belief that this plant furnishes the true officinal Rhubarb. Pe- 

 reira says, that having carefully washed and dried the roots of the most of 

 the species noticed in the foregoing pages, he found that of the R. palmatum 

 closely resembled the Asiatic Rhubarb, in odour, colour, and marbling, 

 and Guibourt declares of all the cultivated kinds, this species alone has roots 

 which resemble in all parts, the Rhubarb of China. Stephenson and Churchill 

 say that it is cultivated largely in England for the roots, but most certainly 

 what is termed English Rhubarb differs very widely from the Asiatic drug, 

 and Royle states that what is grown at Banbury is the R. rhaponticum. 



From the foregoing account it will be seen that it is very uncertain to 

 what species of Rheum the Rhubarb of commerce is to be attributed, and 

 that the probability is, that it is not yet known to botanists. It has, however, 

 been ascertained that it principally grows in Chinese Tartary. From the 

 information obtained by Bell, (Travels, i. 311,) Du Halde, Sievers, and 

 others, it appears that the roots are dug up during the summer season, and 

 only those plants are selected which are five or six years old. The roots 

 are then cleansed, deprived of their cortical portion, cut into pieces, pierced 

 through their centre, strung upon a cord and dried in the sun. In China it 

 is said the pieces are partially dried on a kind of oven, before they are bored. 

 According to Sievers the drying process is very tedious, and that it is some- 

 times a year before the root is fit to offer for sale. 



There are several kinds of Rhubarb recognised by pharmaceutic writers, as 

 the Chinese, Russian or Turkey, Bucharian, Siberian, Himalayan, English 

 and French, the first two of which are those most generally employed in this 

 country. 



Chinese. — This is the sort usually to be met with in the shops, as although 

 not equal to the Russian, still, when of good quality, it answers perfectly well, 

 and can at the same time, be afforded at a much lower price. It is in pieces 

 of various forms, usually cylindrical or rounded, and sometimes flat on one 

 or both sides. Pereira has described three varieties : one he terms Dutch 

 trimmed ; in this the bark appears to have been cut off, and not removed by 

 scraping ; the second, or Chinese Rhubarb, is irregular in shape, never 

 angular, but presenting an appearance of having been scraped ; the third, or 

 Canton stick Rhubarb, is in cylindrical pieces of about two inches in length, 

 and from a half to three-quarters of an inch in diameter. All these are to 

 be met with in our shops, and may be observed in the same parcel. This 

 Rhubarb when good, is rather heavier than the Russian, has a somewhat 

 compact texture, and its fracture is uneven ; the veins especially towards the 

 centre are not regular, and are of a duller colour. It has a peculiar 

 odour, and an astringent somewhat bitter taste, feels gritty when chewed, and 

 tinges the saliva of a yellow colour. 



Russian. — This, as previously stated, is delivered to Russian agents at 

 Kiachta, whence it is taken by caravans to St. Petersburg and Moscow. 

 The pieces vary in shape, and are often angular, from the cortical portion 

 having been cut off, and not removed by scraping. They are smooth and 

 of a yellow colour; they are less compact and heavy than the Chinese, of a 

 livelier colour internally. Their fracture is uneven, marbled with white and 

 red veins, which towards the centre assume a radiated form. The taste is 

 rather more aromatic than the Chinese, but the odour is much the same ; 



