ON QUINONE. WALLACE. 303 



This- precipitate was filtered, washed with ether in which it 

 was insoluble, and dried on a filter-paper. The brown powder 

 remaining readily dissolved in ethyl and methyl alcohols and 

 acetone, forming a brown solution, which on evaporation left 

 a black enarnel-like residue. It was insoluble in water, and 

 all other common organic solvents, but those mentioned 

 above. It was impossible to obtain it in a crystalline form, 

 but a precipitation of it \vas obtained by adding water to a 

 concentrated alcoholic solution and evaporating until little 

 or no alcohol remained. This process was not satisfactory, as 

 the compound separated as a colloid in pure water. This sub- 

 stance was not further studied. The total yield from the 

 experiment was only about 0.5 gram. 



On evaporating the ethereal solution in a porcelain dish, 

 there remained a green crystalline substance in the central 

 part, with a brown amorphous mass surrounding it. The 

 crystals were removed and in order to obtain more of them 

 the amorphous mass was redissolved in ether and again evap- 

 orated. This mechanical process of separation was repeated 

 until a quantity of the crystals was obtained. They were 

 recrystallized from ether and a pure-looking product obtained 

 with a practically constant melting point of 170C. 



An analysis gave the following results : 

 0.1501 gram of substance gave 0.3646 gram CO, and 0.0609 

 gram H O. 



Calculated for Found. 



C^tTioO-i. I 



C 66.02$ 66.29$ 



H 4.63$ 4.51$ 



The green crystals gave tests for a quinhy drone ; the 

 analysis prove it to be of the formula (\ s tT 10 O 4 , or ordinary 

 quinhy drone. 



The remaining amorphous tarry residue left from the ether 

 solution consisted of free iodine, some quinhydrone and re- 



