constituent Parts f)f astringent Vegdahles. 0\) 



the fluid a soft substance was obtained, of a yellowish- 

 brown colour, and of a slightly sourish taste. It was soluble 

 in water, and precipitated the nitro-muriatc of tin, and the 

 nitrate of aluniine ; so that its properties approached to 

 those of extractive matter ; and it probably contained oxalic 

 acid, as it rendered turbid a solution of muriate of lime. 



When a very weak solution of nitric acid was mixed with 

 the infusion, a permanent precipitate was formed ; and the 

 residual liquor, examined by the solution of gelatine, was 

 found to contain tannin. 



A solution of pure potash was poured into a portion of 

 the infusion. At first a faint turbid appearance was per- 

 ceived ; but by agitation the fluid became clear, and its 

 colour changed fromVeliow-brown to brown-red; and tliis 

 last tint. was most vivid on the surface, where the solution 

 was exposed to the atmosphere. The solution of isinglass 

 did not act upon the infusion modified by the alkali till ati 

 acid was added in excess, when a copious precipitation was 

 occasioned. 



The compound of potash and solution of galls, when eva- 

 porated, appeared in the form of an olive-coloured mass, 

 which had a faint alkaline taste, and which slowly deli- 

 quesced when exposed to the air. 



Soda acted upon the infusion in the same manner as pot- 

 ash; and a fluid was formed of a red-brown colour, which 

 gave no precipitate to gelatine. 



Solution of ammonia produced the same colour as potash 

 and soda, and formed so perfect an union with the tannin 

 of the infusion that it was not acted upon by gelatine. 

 When the compound liquor was exposed to the heat of 

 boiling water, a part of the annnonia flew oH', and another 

 part reacted upon the infusion so as to efl'ect a materia,! 

 change in its properties. A considerable quantity of inso- 

 luble matter was formed, and the remaining liquor con^ 

 tained little tannin and gallic acid, but a considerable por- 

 tion of a substance that precipitated muriatv of tin and the 

 salts of alumine. 



Wlien the experiment on the ebullition of the compound 

 of tlic infusion and ammonia was made in close vessels, the 

 lifpior that came over was strongly impregnated with am- 

 iTionia; its colour was light yellow, and, when saturated 

 witli an acid, it was very little altered bv the salts of iron. 

 'J'he residual fluid after the process had been continued for 

 Kome time, as in the other case, precipitated gelatine slightly, 

 but the salts of alumine copiouslv) and it gave a tinge of 

 red to litmus paper, 



K 3 Whea 



