SECTION FOUR 



HAEMATOXYLIN (Regaud) 

 For mitochondria 



Solutions required: 



A. Formalin (40% formaldehyde) . . 25 ml. 

 Potassium dichromate . . • • 3 gm- 

 Distilled water . . . . . . 98 ml. 



B. Potassium dichromate 25% aqueous. 



C. Ammonia - ferric alum 10% aqueous. 



D. Haematoxylin (Regaud). 



E. Iron Alum 5% aqueous. 



Technique: 



1. Small pieces of tissue are fixed for three to five days in Solu- 

 tion A, which should be freshly prepared and changed each day. 



2. Mordant by immersing for ten to fourteen days in Solution B. 



3. Wash in running water for twenty-four hours. 



4. Dehydrate by immersing in ascending grade of alcohol, and 

 clear in the usual manner. 



5. Embed in paraffin wax and cut sections no thicker than 5//. 



6. Fix sections to slides ; de-wax and pass through descending 

 grades of alcohol down to water. 



7. Mordant sections for one to three days in a stoppered jar 

 in the incubator at 37° C. 



8. Rinse for five minutes or so in running water. 



9. Immerse for twenty-four hours in the haematoxylin (Solu- 

 tion D). 



10. Differentiate in Solution E, controlling at intervals by 

 examination under the microscope. 



11. Rinse in running tap water for twenty to thirty minutes. 



12. Drain off excess water; then rinse with 95% alcohol. 



13. Dehydrate with absolute alcohol. 



14. Clear in xylol and mount. 



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