SECTION TWO 



Orange G and Light green solutions. Shake 

 thoroughly. 



Note: This solution keeps indefinitely. 



I. Acetic Acid o-2% 



Technique: 



1. Fix in solution A for 24 hours. 



2. Wash in running tap water for six to eight hours. 



3. Dehydrate, clear and embed in paraffin wax in the usual 

 manner. 



4. Cut sections, in the horizontal plane, 3 to 4/^ in thickness. 



5. Remove paraffin wax from sections with xylol. 



6. Pass through the usual descending grades of alcohol to dis- 

 tilled water. 



7. Immerse in Lugol's iodine for thirty minutes. 



8. Transfer to the sodium thiosulphate solution until the 

 sections have regained their natural colour (about two minutes). 



9. Rinse thoroughly in distilled water. 



ID. Stain in the aldehyde-fuchsin solution from two to ten 

 minutes, taking care not to overstain, which can be avoided by 

 checking the slides (after rinsing in 95% alcohol) at intervals under 

 the microscope: the staining should be stopped as soon as the 

 beta cells stand out clearly in dark purple against a colourless or 

 faintly purple background. 



11. Rinse in two changes of 95% alcohol. 



12. Immerse for five to ten minutes in a third change of 95% 

 alcohol. 



13. Rinse in 70% alcohol. 



14. Rinse in distilled water. 



15. Stain in Ehrlich Haematoxylin for three to four minutes. 



16. Rinse in distilled water. 



17. Differentiate by dipping three or four times in the acid 

 alcohol solution F. 



18. Blue in the lithium carbonate solution; or in running tap 

 water for five to ten minutes. 



E 117 



