OF ARTS AND SCIENCES. 365 



I. 0.1628 grm. of substance dissolved in hydrochloric acid and precip- 

 itated with sodic hydrate gave 0.0356 grm. of cupric oxide. 

 11. 0.2564 grm. gave 0.0596 grm. of cupi'ic oxide. 



Calculated for Found. 



[Cu(NHa)4]3[(SO,,)3C«H3]2. I. II. 



Copper 18.57 17.46 18.57 



No better agreement between these results could be expected, when it 

 is remembered that the substance could not be recrystallized. It is 

 evidently cuprammonic benzoltrisulphonate, but we were unable to 

 prepare it by the action of cuprammonic sulphate on a solution of 

 potassic benzoltrisulphonate. 



Several attempts to obtain the imide [C^^Q{^On)^.-,{'^}i).,, although 

 they led to no definite results, may be mentioned here. The benzol- 

 trisulphochloride mixed with absolutely dry benzol and the silver salt 

 of benzoltrisulphamide, and heated to 100° in a sealed tube for two 

 days, remained entirely unaltered. The experiment could not be re- 

 peated at a higher temperature for fear of decomposing the silver salt. 

 If the chloride was heated with the amide, in the proportion of one 

 molecule of each, to 190°, there was no action; but if the temperature 

 was raised to 200°-210'^, and maintained at this point for some hours, 

 hydrochloric acid was given off, and a black product formed, which, 

 when treated with cold water, swelled up to a gelatinous mass, the 

 water becoming acid with hydrochloric acid. The jelly thus obtained, 

 after being thoroughly washed with water, dried to a more or less 

 colored powder, insoluble in all the solvents that we have tried, so 

 that we have not been able to purify it properly for analysis. Some 

 nitrogen determinations made with a substance extracted with all the 

 common solvents gave results not far lemoved from the numbers 

 required by the imide ; but they are entitled to little, if any, confi- 

 dence, as the substance still contained some chlorine. We satisfied 

 ourselves by a special experiment that the substance mentioned above 

 was not formed from the benzoltrisulphamide alone, since the amide 

 was not altered by heating it to a temperature of 230° for an hour 

 and a half. 



BenzoylbenzoUrisulphamide, CgH3(S02NHCOCgH.)3. 



Benzoylchloride has no action on benzoltrisulphamide when the two 

 substances are heated together on the water-bath ; if, however, the 

 mixture of these substances in the proportion of three molecules of 



