SECTION TWO 



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

 to Best's carmine solution (formula 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. 



1 1 . Clear with xylol and mount. 



Results: 



Glycogen is stained as brilliant red granules, while nuclei are 

 blue. 



BENZIDINE 

 For brain capillaries 







Solution 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 



Hydrogen peroxide 20 vols. 



100 ml. 

 1-5 ml. 



Technique: 



1. Tissue should be fixed for one to three weeks in 10% for- 

 malin and frozen sections, 200 to 300^ should be employed. 



2. Immerse in several changes of distilled water for a total 

 period of two hours. 



75 



