MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



B. Potass, hydroxide N.20 . . . . 6-25 ml. 

 Distilled water . . . . . . 93-75 ml. 



C. Solution A . . . . . . 10 ml. 



Solution B . . . . . . 0-25 ml. 



Note: Solution C should be freshly prepared as 

 required. 



Technique: 



1. Blocks not exceeding 3 mm. in thickness of fresh tissue from 

 the hippocampus major and cerebellum should be fixed in Zenker 

 for twelve to twenty-four hours. 



2. Remove mercurial precipitate with iodine in alcohol by the 

 usual method (see page 28) ; then wash in running water for three 

 to six hours. 



3. Dehydrate in dioxane (see page 36) and embed in paraffin 

 wax. 



4. Sections not more than 4/x thick are mounted on slides and 

 brought down to distilled water. 



5. Flood slides with Solution C and steam gently for five min- 

 utes ; then cool and wash rapidly in tap water. 



6. Decolorize and differentiate each section separately by 

 waving the slide gently in a jar of 90% alcohol until the section 

 assumes a faint violet colour. 



7. Dehydrate rapidly in 95% and absolute alcohol; clear in 

 xylol and mount. 



Results: 



Negri bodies, deep red ; granular inclusions, dark blue ; nucle- 

 oli, bluish black; cytoplasm, bluish violet; erythrocytes, dull 

 reddish brown. 



METHYLENE BLUE - BASIC FUCHSIN 

 For rickettsia in sections 



Solutions required: 



A. Methylene blue 1% aqueous. 



B. Basic fuchsin 0-5% aqueous. 



C. Citric acid 0*5% aqueous. 



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