200 PROCEEDINGS OF THE AMERICAN ACADEMY. 



is undoubtedly accounted for by the difficulty in purifying these amor- 

 phous and infusible substances ; our analyses, therefore, amount only to 

 qualitative proofs of the presence of nitrogen. The introduction of the 

 nitrogen, however, makes it highly probable that both the original 

 substance and its tribenzoyl derivative contain oxygen atoms in the 

 quinone position. We feel justified from the results of the foregoing 

 experiments in assigning to the black alteration product the formula 

 02(110) H2C6-C6H3(OH)2, in which two of the hydroxyl groups are prob- 

 ably in the ortho position to each other, since the substance forms a stable 

 lead salt when treated with plumbic acetate. 



We have made no progress toward determining the position of the third 

 hydroxyl group, which may even be attached to the other benzol ring. 

 The introduction of this third hydroxyl group is not without analogy, 

 since the dinaphthylorthoquinone C10H5O2-C10H5O2 is converted by the 

 action of the air on its solution in weak alkali into the dioxy compound 

 C10H4OHO0-C10H4OHO2.* In our case, however, the oxygen of the air 

 took no essential part in the reaction, as the same alteration product was 

 formed in an atmosphere of carbonic dioxide ; and this is not surprising, 

 as we have had frequent occasion to observe that the orthobenzoquinone 

 is a mucb stronger oxidizing agent than the orthonaphthoquinone, so that 

 one portion of it might easily oxidize the other during the polymerization. 

 The portions of the orthoquinone which gave up oxygen during the 

 formation of the black body were undoubtedly converted into the brown 

 substances soluble in chloroform, which made up about half of the total 

 product. 



Although, as has been already stated, we could not obtain the ortho- 

 quinone in the solid state, many of its properties can be determined 

 from the study of its solution in chloroform ; thus, there can be little 

 doubt that it has an intense red color and little if any odor, as the 

 solution smelt of nothing but chloroform, whereas a smell as strong as 

 that of paraquinone could have been detected even in presence of 

 the amount of chloroform used. Its very slight stability has been 

 dwelt on at sufficient length already, but we should add that it seems 

 to be decomposed at once by even small quantities of water or alcohol. 



We turn next to the reactions of the solution on which is based our 

 inference that it contained orthoquinone. Hydrochloric acid converted 

 it into monochlorpyrocatechine, which, however, was mixed with a little 

 pyrocatechine, as would be expected, since Wichelhausf has shown that 



* Korn, Ber. d. chcm. Ges., XVII. 3021. 

 t Ber. d. chem. Gcs., XII. 150i. 



