SECTION THREE 



Solutions required: 



A. Gelatine 5% 



Gelatine . . . . . . 5 gm. 



Phenol 1% aqueous . . . . 95 ml. 



Warm in an oven to about 45° C. then stir until the 

 gelatine has dissolved; raise to about 60° C. before filter- 

 ing through fine calico. 



B. Gelatine 10% 



Phenol I % aqueous . . . . 90 ml. 



Gelatine . . . . . . 10 gm. 



Prepare exactly as for Solution A. 



C. Gelatine 15% 



Phenol 1% aqueous . . . . 85 ml. 



Gelatine . . . . . . 15 gm. 



Prepare exactly as for Solution A, except that tem- 

 perature should be raised to about 75° C. before filtering. 



D. Gelatine 20% 



Gelatine . . . . . . 20 gm. 



Phenol I % aqueous .. .. 80 ml. 



Prepare as for Solution A, but raise temperature to 

 95° C before filtering. 



E. Gelatine 1% 



Gelatine . . . . . . i gm. 



Phenol I % aqueous .. .. 99 ml. 



Dissolve by warming. 



Technique: 



1. Small pieces of tissue, not more than 3 mm. in thickness are 

 fixed for twenty-four hours in 5% formalin in physiological saline. 



2. Wash in running water. 



3. Immerse in 5% gelatine in an incubator at 37° C. for twenty- 

 four hours. 



4. Immerse in 10% gelatine overnight in an incubator at 37° C. 



5. Immerse in 15% gelatine in an incubator for several hours 

 at 37° C. 



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