STAINING, PRACTICAL AND THEORETICAL 



Notes: 



(i) Solutions F, G and H, above, are referred to as Eosin solu- 

 tions, Nos. I, 2 and 3 respectively. Only one of them is required 

 in the technique given below. 



(ii) It is stated in the original paper that it is necessary that 

 the two reagents (eosin and phosphotungstic acid) are ground 

 together in the solid state, otherwise the dye-mordant combina- 

 tion takes twenty-four hours to form. 



Technique: 



1. Slices of hippocampus (Ammon's horn) from brains of 

 cows, dogs and cats with street rabies virus, and hippocampus 

 from brains of mice, inoculated or infected with human rabies, 

 as well as normal material (to be used as controls), are fixed for 

 twenty-four hours in a mixture of one volume of absolute alcohol 

 and two volumes of saturated aqueous mercuric chloride. 



2. Rinse thoroughly in 70% alcohol. 



3. Dehydrate in the usual way and embed in paraffin wax. 



4. Cut sections at 4/{ and place on dry slides previously covered 

 with glycerin albumen fixative. 



5. Remove paraffin wax as usual and carry the preparations 

 through the usual graded alcohols to 70% alcohol. 



6. Treat for the removal of mercuric deposits. 



7. Wash well in tap water. 



8. Stain in solution A for two minutes. 



9. Wash in running tap water for five minutes. 

 ID. Dip eight times in solution B. 



11. Wash for five minutes in running tap water. 



12. Immerse in solution D for one minute. 



13. Wash in running tap water for ten minutes. 



14. Dehydrate by dipping ten times in each of 50%, 70%, 80%, 

 90%, 95% and absolute alcohol. 



15. Stain for eight minutes in solution F or G or H. 



16. Wash thoroughly in distilled water. 



370 



