490 



SCIENCE. 



[N. S. Vol. XIV. No. 352. 



molecule of hydrochloric acid and one of 

 nitrous acid are split ofiE and a condensa- 

 tion takes place with the formation of 

 dinitro phenoxozone. 



The same kind of action takes place with 

 homopyrocatechin and qualitatively the 

 same action results with the other ortho- 

 dihydroxy compounds; protocatechuic ethyl 

 ester, sesculitin, daphnetin, alizarine and 

 nitropyrocatechin. The condensation prod- 

 ucts have been isolated but not in 

 quantity to make satisfactory analyses. 

 Most of them yield brilliant carmine so- 

 lutions when treated with sodium ethylate. 

 The change produced in this way is only 

 superficial since at least in the case of the 

 simplest one, dinitro phenoxozone, the 

 original compound is precipitated on dilu- 

 tion with water. 



The substance produced by action of al- 

 coholic soda on dinitro phenoxozone has 

 been further studied and found to be the 

 strong acid dinitro dioxy phenoxide. 



The substance formed by action of one 

 molecule of pyrocatechin, two of picryl 

 chloride and two of alkali is proven to be 

 dipicryl pyrocatechin by analysis and by 

 the fact that it splits off one molecule of 

 picric acid and one of nitrous acid and 

 yields dinitro phenoxozone. 



24. ' The Constitution of Azoxyben- 

 zene ' : Arthur Lachman. 



Two formulae have been proposed for az- 



oxybenzene : 



O 



(I.) CeHs-N-N-CfiHs (II.) C6H5-N=N-CeH5 



O 



No positive evidence is available for either 

 of these. The author undertakes to show, 

 by a comparison of azoxj^benzene with 

 diphenylnitrosamine, that formula (II.) 

 cannot represent the properties of azoxy- 

 benzene. There is considerable similarity 

 between (II. ) and the structure of diphenyl- 

 nitrosamine ; and since the compounds are 



isomeric, similarity of reaction may also be 

 expected : 



Diphenylnitrosamine 

 CeH^-N-CeHg 

 I 

 N=0 



Azoxybenzene ( ?) 

 CfiHs-N CeHs 



!l/ 



N=0 



With four different reagents (hj^drochloric 

 acid, phenyl-hydrazine, hydroxy lamine, 

 and zinc ethyl) the author obtained prompt 

 and decisive reactions with diphenylnitro- 

 samine under circumstances where azoxy- 

 benzene was unacted upon. From this it 

 is concluded that only formula (I. ) can be 

 regarded as satisfactory for azoxybenzene. 

 This conclusion is strengthened by thermo- 

 chemical data ; the oxidation of azobenzene 

 to azoxybenzene gives off 257 K, whereas 

 all other classes of nitrogen compounds 

 have negative heats of oxidation. This 

 shows that in azoxybenzene the nitrogen 

 and oxygen have attained the maximum 

 saturation of their affinities, 



25. ' The Action of Zinc Ethyl on Mtro 

 and Mtroso-Compounds, A Reply to I. 

 Bewad ' : Arthur Laohman. 



Bewad has recently claimed priority for 

 the investigation of the above-named reac- 

 tion. This priority is unquestioned. But 

 Bewad is mistaken in his explanations of 

 the various' results obtained. He assumes 

 that the nitro and nitroso groups, ISTOj and 

 NO respectively, behave in a manner ex- 

 actly analogous to the carbonyl group, CO. 

 The author shows, on the basis of his own 

 work, that this supposed analogy does not 

 exist ; that certain nitroso compounds show 

 a peculiarly unique behavior with zinc 

 ethyl ; that other nitroso compounds differ 

 from these first, as well as from carbonyl 

 compounds ; and that no reliable conclu- 

 sions whatever can be drawn as yet from 

 the behavior of nitro compounds. There is 

 also some difference of fact to be noted in 

 the work of Bewad and of the author, 

 which calls for further experimentation. 



26. ' Some Hydrochlorated Sulphates ' : 



