48 SPECIFIC METHODS. 



degeneration, staining it a bright red round the blood vessels. 

 "With old amyloid the results are good, but not so striking. 



This was noticed for the first time by "Warwick in my laboratory, 

 when using Rose Bengale in some experiments on ground stains for 

 different tissues. 



Used as above it is an excellent stain for elastic fibres. 



STAINS AND METHODS FOB NERVE CENTRES. 

 NIGROSINE. Aniline Black. Aniline Blue Black. 



Nigrosine, 2 grms. ; Water, 100 cc. 



Particularly useful for staining unhardened sections of 

 brain ; but it will stain equally well sections of spinal cord 

 which have been hardened in Alcohol, 



Sections of hardened material are placed in this for 10 to 

 15 minutes, washed in 90 p.c. Alcohol, cleared and mounted 

 in Balsam. 



ACID FUCHSINE. 



Acid Fuchsine, 2 grms. ; Water, 100 cc. 



Sections of hardened material are placed in this solution 

 for 2 or 3 minutes, washed in 90 p. c. Alcohol, cleared 

 and mounted in Balsam. 



CONGO RED. 



Congo Red, 2 grms. ; Water, 100 cc. 



Sections are placed in this solution for 2 or 3 minutes, 

 washed in 90 p.c. Alcohol, cleared and mounted in Balsam. 



This dye, but little known, is one of the best stains which 

 I have tried for the central nervous system. 



WEIGERT'S METHOD. 



The brain and spinal cord must be hardened in one of the 

 Bichromate Solutions, and completed in Alcohol. 

 For embedding in Celloidin or Gum, see p. 15. 



