[ 396 ] 



Exp. XI. Two fcruples of green vitriol were difrolvedin fix 

 ounces of fpring water ; of this folution twenty drops were re- 

 fpeftively put into four wine glafles, each containing an ounce by 

 meafure of fpring water. To each of thefe was put refpedively 

 one drachm by meafure of the feveral infofions of rhubarb men- 

 tioned in Experiment I. A black or dark brown colour was pre- 

 sently produced in all of them, fo deep as to obfcure the tranf- 

 parency of the liquors, and of courfe prevent any juft comparifon. 

 A clean pen was dipped into each, and fome words written there- 

 with on a card; thofe written with that wherein the infufion of 

 the Eaft-Indian rhubarb had been put, were the darkeft coloured. 

 No. I. and the Turkey were nearly alike : and No. II. conft- 

 derably the paleft. 



Exp.' XII. The fame experiment was repeated, fave that in- 

 ftead of one drachm of the watery infufion, one drachm of the 

 tinfture in reftified fpirits was fubftituted. They all became in 

 a fhort time fo black, as to obfcure all diftinftion. A pen was 

 therefore dipped into each of them, and words written upon a 

 white piece of card pafleboard as In the laft Experiment. The 

 Turkey rhubarb gave the deepeft colour ; next to that the EaA- 

 Indianj next No. I. j and No. II. the paleft of any. 



Experiments with the Rhubarbs, No. I. and No. II. 

 made at the General Hofpital, by Mr. Farnell, 



ih^ Apothecary \ a very Jenfibky accurate ^ and well-, 

 informed Perjon, 



Case I. 



JAMES JENKINS, aged 38, affliaed with a paralytic affec- 

 tion of his lower extremities, and an involuntary difcharge of urine, 

 took of the powder No. II. half a drachm, in two ounces of fimple 

 peppcrmiiit water, at feven in the morning; it produced four 

 evacuations about fix hours after, and operated without griping. 



The 



