SECTION TWO 



5. Transfer the slide to a stoppered staining jar containing 1% 

 Celloidin (Solution C, above), for fifteen minutes. 



6. Transfer to a stoppered jar containing 70% alcohol, after 

 rapidly wiping off the Celloidin from the back of the slides. This 

 operation must be carried out quickly so that the Celloidin is not 

 allowed to dry. Leave in the alcohol from ten to fifteen minutes. 



7. Transfer to Ehrlich haematoxylin and allow the stain to act 

 from two to ten minutes, differentiating if necessary with acid 

 alcohol, controlling under the microscope. 



8. Rinse in water, and without " blueing " in tap water, transfer 

 to Best's carmine solution (recipe as above) and allow the stain 

 to act for five to ten minutes. 



9. Differentiate in Solution D (above) from one to five minutes 

 until the stain ceases to come away from the section. 



10. Transfer to a mixture consisting of equal volumes of ether 

 and absolute alcohol to dissolve out Celloidin and to dehydrate. 



11. Clear with xylol and mount. 



Results: 



Glycogen is stained as brilliant red granules, while nuclei are 

 blue. 

 Reference: Best, F. (1906). 



BENZIDINE 

 For brain capillaries 



Solutions required: 



A. Benzidine base, pure . . . . i gm. 

 Acetic acid 2-5% aqueous . . 200 ml. 



B. Sodium nitroprusside 1% aqueous 



C. Solution A . . . . . . 20 ml. 



Solution B . . . . . . 10 ml. 



Distilled water . . . . . . 70 ml. 



Mix well and filter. 



N.B.: This mixture should be prepared immedi- 

 ately before use. 



D. Distilled water . . . . . . 100 ml. 



Hydrogen peroxide 20 vols. . . 1-5 ml. 



151 



