STAINING, PRACTICAL AND THEORETICAL 



most tissues, it is unsuitable for bulk material as it tends to cause 

 distortion of protoplasmic cells owing to the rapidity of its 

 dehydrating action. 



Technique : 



1 . Wash pieces of tissue, not more than 5 mm. thick and im- 

 merse directly into cellosolve for half an hour, 



2. Immerse in a fresh bath of cellosolve for half to one hour. 



3. Immerse in a third bath of cellosolve for the same time. 



4. Complete the dehydration in a fourth bath of cellosolve for 

 an hour-and-a-half. 



5. Clear in xylol for an hour. 



6. Immerse in a bath of molten paraffin wax for half an hour. 



7. Transfer to a second bath of paraffin wax for an hour. 



8. Complete the infiltration by immersing in a third bath of 

 wax for an hour ; then cast the block and cut sections. 



9. Fix sections to slides ; then remove paraffin wax with xylol. 



10. Rinse in two changes of cellosolve. 



11. Apply the stain; then wash with water, or alcohol. 



12. Immerse for one to three minutes in each of three changes 

 of cellosolve. 



13. Clear in xylol, benzol, clove oil or cedarwood oil. 



14. Mount in balsam, Cristalite or D.P.X. (Lendrum and Kirk- 

 patrick). 



DIOXANE 



For the dehydration and clearing of tissues 



This reagent is a colourless inflammable liquid, solidifying at 

 10° C, miscible with water and paraffin wax, alcohol and xylol 

 as well as many other organic solvents of the aliphatic and of 

 the aromatic series. It is used and preferred by many workers 

 in place of the orthodox alcohol-xylol-cedarwood oil method for 

 dehydrating and clearing tissues, as the technique is simpler and 

 quicker. It also has the advantage of eliminating brittleness and 

 shrinkage of tissues. Very recently I have found that certain 



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