SECTION ONE 



AZO BLUE 



Michrome No. 300. Molecular weight 727. An acid dis-azo 

 dye, pH 8-9*. Solubility at 15° C: water 2-5%, absolute alcohol 



0-02%. 



CH3 OH 



N=N 



N=N 



CHs 



SOsNa 



BIEBRICH SCARLET, AQUEOUS 



Michrome No. 53. Molecular weight 556. An acid dis-azo dye, 

 pH 8 • I * . Solubility at 15° C : water ^^/q, absolute alcohol 0-25%. 



SOsNa OH 



N=N 



N=N 



SOaNa 



BISMARCK BROWN Y 



Michrome No. 334. Molecular weight 384. A basic dis-azo dye, 

 pH 2-65*, Solubility at 15° C: water 1-5%, absolute alcohol 3% 



H2N- 



N=N 



,— N=N 



NH2 



NH2,HC1 NH2,HC1 



* 1% in neutral distilled water; see pages 17 and 29. 



43 



