SECTION ONE 



PARAROSANILINE CHLORIDEf 



Michrome No. 722. Molecular weight 329. A basic triphenyl- 

 methane dye, pH 6-2S* Solubility at 15° C; water 1%, absolute 

 alcohol 10%. 



H2N 



NH2 



NH2 



ci- 



PATENT BLUE A 



Michrome No. 201. Molecular weight 14084 An acid tri- 

 phenyhnethane dye, pH6-^*. Solubility at 15° C; water 5%, 

 absolute alcohol 7*75%. 



I-O3S 



Ca++ 



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



t Note: This is one of the three component dyes of basic fuchsin. 



J Note: A molecule of this dye consists of two univalent dye-ions in associ- 

 ation with one divalent cation (Ca++). 



In solution such dyes ionize to produce two separate dye-ions, each capable 

 of separately associating with one univalent cation to form a dye of approxi- 

 mately half the molecular weight of the original. 



71 



