Certain New Derivatives in the Aromatic Series. 187 



When coupled with equal molecules of Dahl's acid, naphtylamine- 

 sulphonic acid, 2 : 5, a red dye was produced. Specimen is annexed, 

 labelled No. 16. 



When combined with Neville and Winther's acid, naphtol-sul- 

 phonic acid, 1 : 4, a crimson dye was made. Specimen No. 17. 



When coupled with the technical mixture of beta and gamma 

 naphtylaminesulphonic acids, a brown-red was produced. Speci- 

 men No. 18. 



All the dyes. No. 16, No. 17, No. 18, are precipitated by the addi- 

 tion of common salt, then filtered out and dried. 



V. The fact that Schoellkopf's acid, alphaNaphtoldisulphonic 

 acid, 1:4: 8, gave nearly, if not quite, the fastest of the colors 



SO3H OH 



SO3H 



of the Azo Group, was proved by a series of experiments for 

 other dyes. Bronner's acid, or naphtylamine-sulphonic acid, 2 : 6, 

 was worked upon for new derivatives, and although it has been 

 used with a-Naphtol for Fast Brown .3B; and with beta-Naphtol 

 for Double Brilliant Scarlet ; and with Neville and Winther's acid, 

 naphtol-sulphonic acid, 1 : 4, for Double Scarlet Extra ; yet it was 

 found that other combinations were feasible, and that among half a 

 dozen other new derivatives, the best was that obtained when the 

 Schcellkopf's was used. There a red was given which was very fast 

 to the action of sunlight. Analysis proves the constitution to be — 



(SO3H 



'-^lo^e ^ ^ (OH 



^^^=^~^i»^* ((SO3H),. 



13* 



