was then evaporated to a small bulk^ neutralized with barium 



carbonate and extracted with ether. The ether, on evaprration, 



left the ester which was crystallized from water and dried 



in a desiccator over sulphuric acid. The anhydrous ester 



agreed in melting point (156°-159°) and other properties 



1 

 with the ester of gallic acid described by Grimaux • For 



the sake of comparison, an ester was made from gallic acid 

 obtained from another source and the two agreed in properties. 

 A mixture of the two esters melted within the limits given 

 for the ester of gallic acid. 



While the tests leading to the identification of gallic 

 acid were being made, another aeries of experiments was in 

 progress. Eleven and one-hsilf grams of the resin obtained 

 from lead precipitate A by decomposition with hydrogen sul- 

 phide were treated with 0. In. potassium hydroxide added 

 from a burette until the acid was exactly neutralized. All 

 went into solution. On shaking with ether some of the po- 

 tassium salt sep&rated out and was saved for examination. 

 The solution became brown on exposure to air and got darker ^ 

 as the work proceeded. The acid in solution as a potas- 

 sium salt was precipitated out in four fractions by adding 

 for each fraction one-fourth the amount of Bin sulphuric 

 acid required to neutralize the potassium hydroxide used. 



1. Bull. 3oc. Chim. (II) Vol. 2, 95 (1864). 



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