D. Picric acid, saturated aqueous . . 27 ml. 

 Sodium sulphate saturated 

 aqueous . . . . • • 3 nil. 



Technique: 



1. Fix thin slices of the material in absolute alcohol. 



2. Immerse for one-and-a-half to two hours in each of three 

 changes of acetone. 



3. Transfer to a mixture of equal volumes of acetone and benzol 

 for half an hour. 



4. Immerse in pure benzol for one half to one hour ; then embed 

 in paraffin wax. 



5. Fix sections to slides and de-wax with xylol. 



6. Pass through absolute, followed by 90% alcohol. 



7. Immerse in Solution B in a grooved staining jar for five 

 minutes, rocking gently, but continuously, during the period of 

 staining. 



8. Rinse thoroughly with absolute alcohol. 



9. Stain for half a minute in the methylene blue solution. 



10. Rinse with absolute alcohol. 



11. Stain for fifteen to thirty seconds in Solution D keeping 

 the slides in motion by rocking. 



12. Dehydrate thoroughly with absolute alcohol; clear in xylol 

 and mount in balsam or cristalite. 



Results: 



Nuclei are stained greyish blue, while cytoplasm is yellowish; 

 uric acid crystals are deep greenish blue; monosodium urate, 

 brilliant green. 



H 



87 



