SECTION TWO 



Technique: 



1. Fix pieces of tissue in any desired fixative, and embed in 

 paraffin wax. 



2. Fix sections to slides and dewax with xylol. 



3. Pass through the usual graded alcohols, using the iodine and 

 sodium thiosulphate procedure for the removal of mercurial 

 precipitate, if tissues have been fixed in a mercury-containing 

 fixative. 



4. Wash with water. 



5. Oxidize in the periodic acid solution for ten minutes. 



6. Wash for five minutes in running water. 



7. Immerse in solution B (Schiff's reagent) for ten minutes. 



8. Immerse for two minutes in each of two changes of the 

 potassium metabisulphite (solution C). 



9. Wash for five minutes in running tap- water. 



10. Stain for two minutes in a freshly prepared mixture 

 consisting of equal volumes of Weigert's haematoxylin No. i and 

 No. 2. 



11. Wash in running tap-water for four minutes. 



12. Stain for six minutes in solution F (picro-aniline blue). 



13. Differentiate in two changes each of 95% alcohol and ab- 

 solute alcohol. 



14. Wash in a mixture consisting of equal parts of absolute 

 alcohol and xylol. 



15. Mount in D.P.X., Cristalite, Clearmount or Emexel. 



Results: 



Nuclei: black or dark grey. Collagen: blue. Cytoplasm and 

 muscle cells: greyish green to yellowish green. Chromaffin 

 cells: partly red and partly blue. Amyloid: pink to light purplish 

 red {Note: if the amount of aniline blue in reagent F is increased 

 to 0-4 gm., amyloid is stained blue- violet). Muscle reticulum and 

 epithelial basement membranes: blue or dark violet, and occa- 

 sionally red. Lymphoid tissue reticuHn: blue. Particularly strik- 

 ing results are given in certain chronic nephropathies. Casts are 

 coloured deep purple, intact convulated tubules stain a light 

 yellowish green with red to purple cuticular margin and deep 

 purplish red basement membrane. Connective tissue between 

 both cortical and medullary tubules is stained bright, clear blue. 



131 



