OF ARTS AND SCIENCES. 315 



with a mixture of ortho- and parachlorbenzylchloride, and confirmed 

 the results of Beilstein, as the melting-point of his crystals was 

 84°-85°. In repeating their work, we found that on mixing alcoholic 

 solutions of parachlorbenzylbromide and KSH (prepared by satu- 

 rating an alcoholic solution of potassic hydrate with sulphuretted 

 hydrogen), heat was given off, and the action was finished without 

 the aid of external heat in about half an hour ; on adding water to 

 the product, a dark-colored oil was precipitated, which, purified by 

 distillation with steam, was frozen by immersion in ice and salt, and 

 recrystallized from alcohol with the aid of a freezing mixture. 



0.2560 gr. of the substance dried in vacuo, treated by the method 

 of Carius, gave 0.2276 gr. of AgCl and 0.37.50 gr. of BaS0 4 . 



At ordinary temperatures, it is a colorless liquid with a most repul- 

 sive and nauseating smell ; in a freezing mixture of ice and salt, it 

 solidifies in white crystals, which melt from 19° to 20°. We are not 

 certain that this is the true melting-point of the substance, as a small 

 portion of it may have been converted into the disulphide by the 

 action of the air, and the elementary analysis cannot show the pres- 

 ence of this impurity, but the number here given cannot be very far 

 from the truth, as we got in no case a melting-point much above 20°, 

 and the substance was reduced with zinc and dilute sulphuric acid, so 

 as to convert any disulphide into mercaptan, before taking some of the 

 melting-points. It distils with steam, and mixes readily with alcohol, 

 ether, benzole, and carbonic disulphide, but not with water. Yellow 

 mercuric oxide attacks it with great energy, and converts it into the 

 following compound. 



Parachhrbenzyhnercaptid, (C e H 4 ClCH 2 S) 2 Hg, was purified by re- 

 peated crystallization from boiling alcohol. 



0.4820 gr. of the substance dried in vacuo gave by precipitation 

 with H 2 S 0.2175 gr. of HgS. 



Calculated for (C 7 H 6 ClS) 2 Hg. Found. 



Mercury 38.84 38.91 



It forms light white needles without odor, which seem to have no 

 definite melting-point, although the substance turns red or black, and 

 shrinks to about one half of its original volume in the neighborhood 



