274 PROCEEDINGS OP THE AMERICAN ACADEMY. 



time with constant stirring. The beaker w ed by immersing it in 



ice. The precipitate was washed with benzol until the filtrate was color 

 less, and then dried on :i porous plate and in vacuo. Analyses I. and II. 

 are of two different products prepared in this way. As in these prepara- 

 tions and the other similar ones described in this paper we bad used tln-ee 

 molecules of the .-odium compound to one of the nitro body, there Beemed 

 Borne danger that our products might be nol definite compounds, but 

 mixtures of an addition compound containing only one atom of Bodium, 

 with the two additional molecules of the sodic malonic ester (or the 

 corresponding reagent) precipitated by the large excess of the benzol. 



This objection to our results did not seem a \«r\ importanl because 



the} agreed better with the theoretical numbers than would be probable if 

 this theory were true, but we felt that it was necessary to tesl it by ex- 

 periment, ami for this purpose repeated the preparation, using two mole- 

 cules of sodic malonic ester to each molecule of trinitrohenzol < I gram of 

 trinitrobenzol and 1.7 grams of the sodic malonic ester). Analysis III. 

 was made with the specimen prepared in this way. and proves that our 

 suhstances are definite compounds and not mixtures, since it agrees with 

 those prepared with three molecules of the sodium ester. 



I. 0.2038 gram of the Bubstance gave 0.05 1 1 gram of sodic sulphate. 



II. 0.2 lo 1 gram of the substance gave 0.0590 gram of sodic sulphate. 



III. 0.2G30 gram of the substauce gave 0.0756 gram of sodic sulphate. 



Calculated for 



C II 3 (NO,t eiiv, OOOOA)&1» 



Sodium 9.09 



Properties of the Addition Product of Trinitrobenzol and Sodic Malonic 

 Ester, C c II,(NO,).,[CI I Nai ( !< K K ,1 1, >„],. 



This body has a rich maroon color brighter than that of the corre- 

 sponding compound of trinitranisol and sodic malonic ester. It is stable 

 for some time if kept dry and cool, otherwise it gradually undergoes 

 decomposition, as shown by its change of color and becoming gummy. 

 In its other properties it resembles the corresponding trinitranisol coin- 

 pound most closely. When treated with hydrochloric acid the color is 

 destroyed, and a thick oily brownish yellow precipitate is formed, by 



washing this with small quantities of alcohol to remove the malonic ester 

 the trinitrobenzol was recovered in quantity, and recognized by its 



melting-point, 121°-122°, after recrystallization from benzol. As soon, 

 therefore, as the three atoms of sodium are replaced by hydrogen, the 

 addition product splits into its constituents. 



