OF ARTS AND SCIENCES. . 185 



was made from a quantity of tribromtriuitrobenzol, tlie purity of 

 which had been proved by analysis in addition to the melting jjoint, 

 found 53. GO per cent of bromine instead of the 53. 33 per cent re- 

 quired by the formula. 



As potassium compounds behave in many respects differently from 

 the corros{)ouding sodium compounds, we have repeated the experi- 

 ment with potassic in place of sodic ethylate, but with the same 

 result, that is, tribromnitroresorcine diethylether melting at 101° 

 and potassic nitrite. 



Pruperlies of Tribromnitroresorcine Diethylether, C^t^O./OC.^I^.;,. 

 — This substance forms well developed white flat prisms, usually with 

 square ends, but sometimes terminated by two planes at an obtuse 

 angle. It melts at 101°, and is very slightly if at all soluble in water, 

 whether cold or hot ; easily soluble in cold ethyl or methyl alcohol, 

 still more freely in hot; very freely soluble in chloroform ; freely in 

 benzol; soluble in ether, acetone, carbonic disulphide, or glacial acetic 

 acid; slightly soluble in ligroine. Hot alcohol is the best solvent for 

 it. The three strong acids seem to have no action on it, whether they 

 are hot or cold. Aniline dissolves it, but has no other action on it at 

 ordinary temperatures, or even at 150° ; at higher temperatures a sub- 

 stance similar to rosaniline is formed. A mixture of malonic ester and 

 sodium malonic ester was allowed to stand for several weeks with an 

 alcoholic solution of this substance ; but, although at the end of this 

 time the liquid had assumed a slight reddish color, and a little .sodic 

 bromide (but no nitrite) had been formed, the action was so limited 

 that the only organic compound which could be detected in the product 

 was unaltered tribromnitroresorcine diethylether melting at 101°. It 

 appears from these experiments that the tribromnitroresorcine diethyl- 

 ether is not an especially reactive substance, and yet when it was 

 boiled with an alcoholic solution of sodic ethylate a reaction took place, 

 as was shown by the dark color which the solution assumed, and the 

 formation of a considei'able amount of sodic nitrite, proved by the test 

 with potassic iodide, starch, and dilute sulphuric acid. Unfortunately 

 the end of the term prevented ns from isolating the organic product, 

 or more probably products, of this reaction, but the work will be con- 

 tinued next year. 



Trihrom dinitrop hen etol, CgB Fg (NO,) ,0 CjH.. 



In our first experiment on the action of sodic ethylate on tribrom- 

 triuitrobenzol the conditions were somewhat different from those 

 described above, which gave us the tribromdinitroresorcine diethyl- 



