308 Dr. Schunck on some Products 



unite with alcohol and indigo-blue, for which it cannot be 

 supposed to have any strong chemical affinity? 



3. The physical properties of these compounds do not seem 

 to depend in any way on those of their constituents. Never- 

 theless it is to be observed that those containing the largest 

 proportion of alcohol are insoluble in alkalies, whilst those in 

 which the indigo-blue preponderates are the least soluble in 

 alcohol and ether. 



4. No law or rule can be detected determining the number of 

 atoms of alcohol and acetic acid which are capable of uniting 

 with the indigo-blue. Were the series more extensive, it is 

 probable that some such law might be found to prevail. It 

 may be remarked, however, that all the products insoluble 

 in water, with one exception, contain either .8 or 10 equivalents 

 of oxygen (assuming the formula of C to be doubled), as will 

 be seen from the following tabular view of their formulas : — 



B IC 40 H 23 N 8 



C C 56 H 22 N 2 8 



D C 56 H 24 N 2 O 10 



E C 28 H n N 6 



5. Regarding the rational formulse or probable internal con- 

 stitution of these compounds I hardly venture to indulge in any 

 speculations. They might be considered as conjugated com- 

 pounds — compounds of which organic chemistry affords so 

 many examples; and it might consequently be possible to 

 obtain from them, by decomposition, some of the simpler bodies 

 which are known to have entered into their composition. I 

 have, however, been unable to discover any facts in favour of 

 this view. Neither indigo-blue nor any of its products of de- 

 composition can be obtained from them by any means which I 

 have tried. In one experiment which I made for this pur- 

 pose, and which consisted in subjecting the body D to the 

 action of caustic soda, I obtained neither anthranilic acid nor 

 acetic acid, as might have been expected. By evaporating the 

 alkaline solution to dryness, and heating the residue to inci- 

 pient fusion, the substance was partly converted into a black 

 humus-like matter, insoluble not only in water and alcohol, 

 but also in alkalies. The alkali was supersaturated with sul- 

 phuric acid, and the liquid was distilled, when a trace of what 

 I suppose to be formic acid passed over. The liquid yielded 

 no anthranilic acid. 



In this respect these compounds resemble some of the secon- 

 dary products which are formed during the decomposition of 



