C 394 ] 



moft of the aromatic tarte. The next in degree was No. I.— 

 No. II. and the Eaft-Indian were nearly alike. 



When become dry and hard, as all the extrafts were in a few 

 days, thofe of the Turkey, and Eaft-Indian rhubarbs affiiraed a 

 clear glofly furface. No. I. was rough, but rather fhining; and 

 No. II. rough and dufky. In point of cohfiftence, thofe of the 

 Turkey and Eaft-Indian rhubarbs were extremely brittle, and 

 broke into clear glofly fmall pieces ; that of No. I. had a ccnft- 

 derable degree of tenacity ; and No. II. ftill more of that quality. 



Exp. IV. Nine grains of the above four extracts, accurately 

 weighed, were put into four feparate tea-cups, and half an ounce 

 by meafure of reftified fpirits of wine poured upon each ; after 

 ftanding fix hours, the fpirits were tinged of a deep yellow colour, 

 darkeft in the Eaft-Indian ; next in the Turkey, next in No. I. ; 

 and No. II. the paleft of any. The fpirits were then poured off 

 from all, and the fame quantity of frefh fpirits add^d, which was 

 repeated five times, at the end of each of which the fpirits Ln all of 

 them were coloured in the order above dffcribed, but much paler 

 than at firft. The refidua from each were then collefted care- 

 fiilly and dried; they were all rather filmy, and mucilaginous la 

 the mouth, and foluble in the faliva, and had but little tafte of 

 any kind. No. I. was of a pale yellow colour and brltde tex- 

 ture, and weighed one grain and three quarters. The Turkey 

 thubarb was of rather a darker colour in general, though inter- 

 mixed with fome of a paler hue, and weighed the fame as No. I, 

 —No. II. was of a lighter colour, and weighed two grains and 

 three-quarters.— The Eaft-Indian refembled the Turkey, and 

 weighed one grain. 



Exp. V. Three drachms of the four kinds of rhubarb men- 

 tioned above, were feverally put into four ounces of rectified 

 fpirits of wine, and corked up ; after feveral days ftanding they 

 were filtered. The Eaft-Indian rhubarb had acquired a dark 

 yellowifh red colour. No. I. and the Turkey had a fimilar tinge, 

 but lighter; and differing but little from one another. No. II. 

 was of a fimilar hue, but lighter ftill. 



ExP. VI. 



