64 W. H. E M I G 



1050. Alizarin Cyanine R is an acid mordant dye. A solution 

 of this dye is not stable and, on heating, a reddish precipitate pre- 

 vents the development of a clear stain. 



1051. Alizarin Cyanine G is a direct mordant dye, light 1; 

 1/10 gram in 100 ml. of 1 per cent ammonium acetate. Sections of 

 plant materials that are mordanted in ammonium alum are stained 

 a clear Hematein-purple. Objects that are mordanted in ferric 

 alum are red-violet to blue-violet within five to ten minutes at 50° C. 

 Blue-green algae are stained purple in alkaline solutions. When 

 ferric alum is used as a mordant, paraffin sections of animal tissues 

 or whole mounts of invertebrates are blue-violet in two to three 

 minutes at 50° C. 



1054. Alizarin Sapphire BN (NAC) is a direct mordant dye, 

 light 2. Sections mordanted in ferric alum show only a trace of 

 color at 50° C. in the ammonium acetate strain ; in the sulfuric acid 

 solution of the dye, nuclei are light blue. 



1067. Alizarin Blue S is a mordant dye, light 3. The dye dis- 

 solves in slightly alkaline 50 per cent alcohol but the blue pigment 

 separates from solution either in the presence of acids, alkalies, or 

 upon heating. 



Class XXIV. Anthraqninone Vat Colouring Matters 



1101. Car banthrene Jade Green (NAC). 



1104. Carbanthrene Violet 2R (NAC). 



1113. Carbanthrene Blue GD (NAC). 



1131. Ponsol Red 5GK (Du Pont). 



Ponsol Red AFF (Du Pont) . 



Carbanthrene Brilliant Orange RK (NAC). 



1162. Carbanthrene Red BN (NAC). 



Sulfanthrene Red 3B (Du Pont). 



A few of the cold vat dyes may be applied to blue-green algae at 

 50-60° C. The preparation of the stain is described under Indigo, 

 CI. No. 1177. 



Class XXV. Arylidoquinone Vat Colouring Matters 

 Class XXVI. Indigoid Colouring Matters 



1177. Indigo is a vat dye, light 1; 1/10 gram of the dye is 



