SECTION TWO 



9. Rinse in 70% alcohol. 



10. Wash in running water for five minutes. 



11. Treat for the removal of mercuric deposits if a mercuric 

 chloride-containing fixative has been used. 



12. Immerse in the periodic acid (solution B) for ten to fifteen 

 minutes. 



13. Wash in running water for five minutes. 



14. Immerse in distilled water for three to five minutes at 35° 

 to37°C. 



15. Immerse in ammoniacal silver (solution H) in an incubator 

 at 35° to 37° C. for one and a half to two hours. 



16. Wash in solution I (ammoniated water) for a few seconds to 

 remove excess silver precipitates. 



Note: It is essential that the sections should not be allowed to 

 come into contact with metals, and the use of metal instruments 

 must therefore be avoided when transferring slides. Silver solu- 

 tions should remain colourless. 



17. Immerse in the " buffered " formalin (solution J) for five 

 minutes. 



Note: Use a fresh solution each time. 



18. Wash in running water for five minutes. 



19. Tone in gold chloride (solution K). 



20. Fix in sodium thiosulphate (solution L). 



21. Wash in running water for five minutes. 



22. Immerse in the orcein (solution M) in a stoppered staining 

 jar in an incubator at 37° C. for fifteen minutes, or at room tem- 

 perature for an hour. 



23. Rinse in 70% alcohol for two to three seconds. 



24. Rinse in distilled water for two to three seconds. 



25. Immerse in 5% phosphomolybdic acid (solution N) for ten 

 to fifteen minutes. 



26. Rinse in distilled water for two or three seconds. 



27. Immerse in aniline blue (solution O) for two to three 

 minutes. 



28. Rinse in distilled water for a second or so. 



29. Immerse in acidulated water (solution Q) for five minutes 

 or longer. 



30. Wash with 95% alcohol. 



31. Dehydrate with absolute alcohol. 



361 



