possessing the Properties of Tannin, 61 



which has been described, and formed a tough yellow pre- 

 cipitate, which was insoluble in boiling water. 



With other reagents the effects were as follow : 



Sulphate ot iron, after i2 hours, formed a slight yellow 

 precipitate. 



Nitrate of lime did not produce any effect. 



Muriate of tin, after 12 hours, afforded a pale brown pre- 

 cipitate. 



And acetlte of lead immediately formed a very abundant 

 precipitate of a yellowish white colour. 



I repeated this experiment on common resin, and re- 

 marked, that during each distillation nitrous gas was pro- 

 duced, whilst the strength of the acid which came over was 

 diminished ; the cause therefore of the change in the pro- 

 perties of the resin seemed to me very evident, and I was 

 induced to extend the experiments to various resinous and 

 other substances ; but as the process was uniformly the 

 same, I shall only notice the principal effects. 



B. Stick lac, when separated from the twigs, and treated 

 as above described, copiously precipitated gelatine. 



C. Balsam of Peru during the process afforded some 

 benzoic acid, and gelatine was precipitated by the aqueous 

 solution. 



D. Benzoin also, after the sublimation of some benzoic 

 acid, yielded a residuum, which with water formed a pale 

 yellow solution of a very bitter flavour. 



This solution witli sulphate of u-on afforded a slight pale 

 yellow prc'cipitate. 



With nitrate of lime not any effect v.-as produced. 



The solution with muriate of tin became turbid, and a 

 small quantity of brownish-whhe precipitate subsided. 



Acetiteof lead immediately produced a copious pale yel- 

 low precipitate. 



And solution of isinglass formed a dense yellow precipi- 

 tate, which wa5 insoluble in boiling water. 



E. Balsam of Tolu, like b:dsam of Peru, and benzoin, 

 afforded some benzoic acid; and the residuum being dis- 

 solved in water was found to precipitate gelatine. 



F. As the rer?ull5 of the e.s'pcriments on dragon'"? blood 



v.vre 



