142 PROCEEDINGS OF THE AMERICAN ACADEMY. 



0.2188 gram of the substance gave by the method of Carius 0.4746 

 gram of a mixture of argentic chloride and iodide. After wash- 

 ing this precipitate with ammonic hydrate 0.1672 gram of argentic 

 iodide were left undissolved. 



The substance is therefore trichloriodbenzol, and as it was made from 

 common trichloraniline its constitution must be Cl3l,3,5,I2. 



Properties of Trichloriodbenzol. — It crystallizes from alcohol in white 

 slender needles terminated by one plane at a very acute angle ; these 

 needles are often a centimetre or more long, and are much branched, the 

 branches forming a sharp angle with each other and developing into 

 forms like feathers. It melts at 55°, and sublimes easily. It is freely 

 soluble in ether, benzol, chloroform, acetone, carbonic disulphide, or 

 ligroiu ; soluble in ethyl or methyl alcohol, when cold, more freely 

 soluble when hot; soluble in glacial acetic acid; insoluble in water, cold 

 or hot. A mixture of alcohol and chloroform is the best solvent for it. 

 It is apparently unaflfected by the strong acids, or by sodic, potassic, or 

 ammonic hydrate. 



Behavior of Trichloriodbenzol with Sodic Ethylate. 



Two fframs of trichloriodbenzol dissolved in anhydrous benzol were 

 mixed with 20 c.c. of an alcoholic solution of sodic ethylate made from 

 one gram of sodium, and the mixture was allowed to stand over night. 

 The liquid turned dark brown, and a precipitate began to separate soon 

 after adding the ethylate. To make certain that the reaction was com- 

 plete, the mixture was heated on the steam bath in a flask with a return 

 condenser, which rendered the brown color much darker. The product 

 was then evaporated to dryness; during the evaporation an odor like that 

 of an aldehyd was observed, but the presence of one could not be deter- 

 mined by other tests. The dry residue was treated with water, and the 

 insoluble portion separated from the solution, which gave tests for an 

 iodide. The portion insoluble in water, which was very dark brown, 

 was washed thoroughly, and then purified by crystallization from alco- 

 hol, until it showed the constant melting point 64°, which proved that it 

 was the symmetrical trichlorbenzol. This was confirmed by the following 

 analyses of the substance dried in vacuo : — 



