OF ARTS AND SCIENCES. 23 



sionally determined direct in the filtrate from the zincic carbonate and 

 silicate by evaporating to dryness in a platinum crucible, and, after 

 removing any slight excess of sodic carbonate by converting it into 

 acetate and washing with 80% alcohol, igniting and weighing as sodic 

 fluoride. 



I. 0.2G8G wm. of the substance gave 19.6 c.c. of nitrogen at a tem- 



O o O 



perature of 23° and a pressure of 768 mm. 

 II. 0.2982 grm. of substance gave 0.0751 grin, of silicic dioxide and 

 0.2105 grm. of sodic fluoride. 



III. 0.2842 grm. of substance gave 0.0717 grm. of silicic dioxide and 



0.1968 grm. of sodic fluoride. 



IV. 0.3784 grm. of substance needed for neutralization 0.2480 grm. 



of sodic hydrate. 



IV. 



31.15 



Several attempts to make a combustion of the substance have shown 

 that great difficulties stand in the way of getting satisfactory results, 

 and, as the determinations of nitrogen, silicon, and fluorine just given 

 are sufficient to establish its formula beyond a doubt, we have not 

 thought it worth while to devote to the study of the conditions of its 

 combustion the time necessary to obtain an accurate result. 



Properties. — The trianiline disilicotetrafluoride is a white semi- 

 crystalline to amorphous solid, which sublimes in the neighborhood of 

 200° without melting. It is insoluble in ether (anhydrous), benzol, 

 ligroine, chloroform, or carbonic disulphide. It is decomposed very 

 slowly by boiling absolute alcohol without any deposition of silicic 

 acid, and converted into aniline fluosilicate ; we have not succeeded in 

 bringing the other product of this reaction into a state fit for analysis ; 

 it is a thick liquid, probably a silicic ethylester. The action is more 

 rapid with alcohol containing water. Water decomposes it at once 

 with deposition of silicic acid, and the solution yields on evaporation 

 aniline fluosilicate* in beautiful white pearly scales. Its identity was 

 determined by the following analysis. 



0.7488 grm. of substance gave by precipitation with baric chloride 

 0.6372 grm. of baric fluosilicate. 



* W. Knop and VV. Wolf, (Jhein. Centralblatt, 18(52, p. 401. 



