340 A P P E N D I X II. 



barb ; and his defcription of that plant anfwered to the 

 figure of the Rheum Rhaponticum. The truth of this 

 defcription was ftill further confirmed by fome Mongol 

 travellers who had been in the neighbourhood of th& 

 Koko-Nor and Thibet ; and had obferved the rhubarb 

 growing wild upon thofe mountains.. 



The experiments alfo made by Zuchert and others, 

 upon the roots of the R. Rhabarbarum and R. Rhapon- 

 ticum, fufficiently prove, that this valuable drug was 

 procured from thofe roots in great perfedtion. But as 

 the feeds of the Rheum Palmatum were received from 

 the father of the above-mentioned Bucharian merchant 

 as taken from the plant which furnifhes the true rhu- 

 barb, we have reafon to conje6ture, that thefe three 

 fpecies, viz. R. Palmatum, R. Rhaponticum, and R. Rha- 

 barbarum, when found in a dryer and milder alpine 

 b^irh""ob^i!i''' climate, and in proper fituations, are indifcriminately 

 .Merenfbpe-" drawu up *, whcncver the fize of the plant feeras to pro- 



cies of Rheum. 



mife a fine root. And perhaps the remarkable dirrerence 

 of the rhubarb, imported to Kiachta, is occafioned by this 

 indifcriminate method of coUeding them. Moft certain 

 it is, that thefe plants grow wild upon the mountains, 

 without the leaft cultivation ; and thofe are efteemed the 

 beft which are found near the Koko-Nor, and about the 

 fources of the river Koango. 



Formerly 



