502 HISTOLOGY 



8 hours. Wash quickly in water. Stain for 12 to 24 hours in a well- 

 ripened solution consisting of 0.5 gm. haematoxylin dissolved in 10 c.c. of 

 absolute alcohol and added to 90 c.c. of water. Wash in water. Dif- 

 ferentiate in the iron alum solution, controlling the result under the micro- 

 scope. The section should be washed in water before each examination. 

 When the stain is limited to the nuclei, and these are sharp, wash in run- 

 ning water for 15 to 30 minutes; 50 per cent.; 70 per cent.; 80 per cent.; 

 95 per cent.; absolute alcohol; absolute and xylol; xylol. 



If a counterstain is desired, add to 95 per cent, alcohol enough of a 

 i per cent, solution of Orange G in 50 per cent, alcohol to give a deep 

 orange color. Transfer the section from 95 per cent, to the stain for a 

 few minutes. Wash well in 95 per cent., and pass through absolute, abso- 

 lute and xylol, to xylol. 



Weigert's Iron Haematoxylin. 



A. Haematoxylin crystals i gm. 



Alcohol, 95 per cent 100 c.c. 



B. Liquor ferri sesquichlorati 4 c.c. 



Water 95 c.c. 



Hydrochloric acid i c.c. 



At the time of using, mix equal parts of A and B. Transfer the sec- 

 tions from water to the stain for 2 to 5 minutes. Wash in water. If 

 the section is overstained, add a few drops of hydrochloric acid to the 

 water. To stop the decolorization, dip in water made alkaline with a 

 little ammonia. This is an excellent stain and gives brilliant results. 

 If a counterstain is desired, place sections for about i minute in Van 

 Gieson's mixture: 



Picric acid, sat. aq. sol , 100 



Acid fuchsin, i per cent. aq. sol 10 



Wash in water; 95 per cent.; absolute; absolute and xylol; xylol. For 

 celloidin sections, 95 per cent. ; oil of origanum. 



Safranin. 



Safranin i gm. 



Absolute alcohol 10 c.c. 



Anilin water 90 c.c. 



Anilin water is prepared by shaking up 5 c.c. of anilin oil in 95 c.c. of 

 distilled water and filtering through a wet filter. Dissolve the safranin 

 in the alcohol and add to the anilin water. 



Safranin is to be used after fixation in Flemming's fluid. Stain thin 

 paraffin sections for 24 hours; wash in water; decolorize in absolute alcohol, 

 to which has been added hydrochloric acid in the proportion 1:1000, 

 until only the nucleus retains the stain; fresh absolute; absolute and 

 xylol; xylol. 



