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the medicine ; and thofe which appear after It has operated 

 as a purgative. The chemical experiments above-recited 

 fhew the exiftence of an aftringent principle in all the 

 rhubarbs, and the degree in which it takes place ; but we 

 cannot from thence draw any certain conclufion with re- 

 fpecl to their operation on the human body. I have known 

 the gum kino, the ftrongeft vegetable with regard to tafte 

 with which we are acquainted, purge more violently than 

 jalap. How far, indeed, the aftringent quality of rhubarb 

 with regard to the bowels is feparable from its power as 

 an aperient, and whether therefore it poflefles that quality 

 in a higher degree than any other purgative equally draftic, 

 experience, I think, has not hitherto afcertained. 



Let us however examine the properties of our different 

 kinds of rhubarb in cafes of diarrhoea, in which alone we 

 can form a true judgment of their effefts. In the ex- 

 am.ples of Gibbons and H. White, the rhubarb No. 11. 

 fhewed an immediate power of diminifhing the number of 

 ftools; for in both there were fewer motions on the days 

 on which it was taken, than on others. This alfo ap- 

 peared from the firft exlubition of the fame rhubarb in the 

 feveral cafes of Greenaway, Jane White, and Allen. 

 No. I. feemed to have the fame property in the cafes of 

 Pye and Saunders ; but the Turkey rhubarb in no inftance. 

 To fliew thefe effects ftill more clearly, we may obferve, 

 that in feven of fourteen experiments made in the above 

 cafes of diarrhuea with the rhubarb No. II. that medicine 

 diminifhcd the number of ftools the day on which it was 

 given; No. I. in two of ten experiments j the Turkey in 



no inftance out of foiir, 



To enter into a difcjuifition concerning the caufe of 

 thefe differences, would belong more properly to a col- 



E c 3 ledjoii 



