5" 



(iv) Cut as thin sections as will remain 

 intact. 



To Stain and Mount Tissues 



1. If the sections are crumpled, float them 

 upon water just hot enough not to melt the 

 paraffin. They will become quite flat. Float the 

 flattened sections on to a clean slide. Remove 

 excess of water, and firmly press a piece of filter 

 or blotting paper over the section. Thoroughly 

 dry by holding a few minutes over the flame (care 

 being taken not to melt the paraffin), or by placing 

 for twenty-hours in a dessicator or warm oven. 

 No further fixative is generally needed. If neces- 

 sary, the slide may previously be smeared with 

 the merest trace of egg-albumen fixative. ; It must, 

 in this case, be dipped rapidly into the water and 

 quickly withdrawn. (Appendix.) 



2. If the sections are flat they may be placed 

 directly upon a slide slightly smeared with fixative. 

 In this case, celloidin in oil of cloves is the best 

 fixative. (Appendix.) 



3. Hold the slide or coverglass with the 

 section over the flame till the paraffin melts. 

 Dissolve off the paraffin with xylol, and then 

 drop alcohol over the section. Place the slide 

 or cover-glass in water. 



4. Stain. —The best stains for general use 

 are : — 



(i) Haematein purissimus, saturated 



solution in 70 per cent, alcohol 10 cc. 

 Alum solution (alum 50 grammes, 



water 1,000 cc.) ... 50 cc. 



