212 PROCEEDINGS OF TBE AMERICAN ACADEMY 



form part of hydroxyl groups ; from the formation of the substance these 

 two atoms of oxygen must either belong to a quiuone, or be the connect- 

 ing atoms of a pyrocatechiue ether, and, as our work on the reduction of 

 the alteration product has shown that it is probable they are not pyro- 

 catechine ether oxygen atoms, there can be little dcubt that they occur in 

 the quinone configuration, which indeed was the more probable supposi- 

 tion of the two. We tried to confirm this inference by the formation of 

 hydrazones both from the original black alteration product and its ben- 

 zoyl derivative, but without satisfactory results. When jDhenylhydrazine 

 in excess was added to a solution of 0.5 gram of the black alteration 

 body dissolved in 10 c.c. of alcohol, the dark blackish color of the so- 

 lution was discharged, and on pouring the product into acidified water a 

 golden yellow precipitate was formed ; but an analysis of the substance 

 gave 6.39 per cent of nitrogen, whereas the most probable formula, 

 C12H8O4NNHC6H5, requires 8.70 per cent of nitrogen. The tribenzoyl 

 derivative of the black substance was dissolved in chloroform, and boiled 

 with an excess of phenylhydrazine for several minutes ; a new com- 

 pound was formed, which was obtained by allowing the chloroform to 

 evaporate spontaneously, treating with an acid to remove the excess of 

 phenylhydrazine, dissolving the residue in cold alcohol, and precipi- 

 tating the substance from this solution with water. After drying in 

 vacuo it was analyzed, and 3.19 per cent of nitrogen found instead of 

 4.42 per cent of nitrogen required by the formula of the hydrazone, 

 Ci2H50(NNHC6Hi3)(OCOC6H5)3. It is evident from these results that 

 phenylhydrazine acts on both of these substances, and that the product in 

 each case contains nitrogen. The results, therefore, as far as they go, 

 confirm our inference that there are two quinone atoms of oxygen in the 

 black substance, but they are of little value, because the exceedingly unman- 

 ageable nature of both of these substances prevented us from purifying 

 them sufficiently to determine their composition with certainty. 



The work just described establishes the following points with tolerable 

 certainty. The black alteration product is a diphenyl compound, and 

 contains three hydroxyl groups and an orthoquinone group ; it may there 

 fore be called orthodioxyphenyloxyorthoquinone, and receive the formula 

 C6H3(OH)2C6H2(OH)02, although the three hydroxyl groups may be 

 attached to the same benzol ring, as we have not determined the position 

 of the third hydroxyl experimentally. 



