STAINING 7 1 . 



Methyl Blue and Safranin. - Methyl blue is ;i very .liilVivnt dye 

 from methylene blue but is practically identical with water blue ( Wassei 

 blau). It is an acid or cytoplasmic stain. 



1. Stain with a 2 per cent, aqueous solution of meth\l blue, three 

 minutes. 



2. Rinse in water. 



3. Stain in a 1 per cent, aqueous solution of sal'raiiin, five minutes. 



4. Wash in water. 



5. Differentiate and dehydrate quickly in absolute alcohol, till the 

 sections become again blue. 



6. Clear and mount. 



This method gives a permanent stain which yields excellent results 

 with certain tissues e.g., the skin. 



Other nuclear and cytoplasmic dyes may be combined in a similar 

 manner to the above methods. 



SPECIAL STAINING METHODS 



Iron Hematoxylin (H eidenhain) : 

 I. Mordant: 



Ferric alum (iron ammonium sulphate violet 



crystals) 2 grin. 



Distilled water 100 c.c. 



II. Stain: 



Hematoxylin 1 grm. 



95 per cent, alcohol 10 c.c. 



Distilled water 100 c.c. 



1. Mordant the sections four to twelve hours in I. 



2. Rinse in water. 



3. Stain twelve to twenty hours in II. 



4. Wash well in water. The sections should become very black; 

 a drop or two of ammonia to one-half liter of water often improves 

 the color. 



5. Decolorize in the mordant, watching each section under the 

 microscope, and stopping the decolorization at the proper time by- 



6. Wash thoroughly in slowly running water, or in several changes 

 of still water. 



7. Counter-stain if desired, dehydrate, clear, and mount. 



