PERMANENT PREPARATIONS 405 



2. Place it in a wide-mouthed stoppered jar, large 

 enough to hold it conveniently, resting on a pad of 

 cotton- wool, and arrange it in the position it is intended 

 to occupy (but if it is intended to show a section of the 

 tissue or organ, do not incise it yet) . 



3. Cover with the Kaiserling fixing solution, and 

 stopper the jar; allow the tissues to remain in this 

 solution for from forty-eight hours to seven days 

 (according to size) to fix. Make any necessary sections. 



Kaiserling modified solution is prepared as follows : 

 Weigh out 



Potassium acetate 30 grammes. 



Potassium nitrate 15 grammes. 



and dissolve in 



Distilled water 1000 c.c. 



then add 



Formalin 150 c.c. 



Filter. 



This fixing solution can be used repeatedly so long 

 as it remains clear. Even when it has become turbid, 

 if simple filtration is sufficient to render it clear, the 

 filtrate may be used again. 



4. Transfer the tissue to a bath of methylated spirit 

 (95 per cent.) for thirty minutes to one hour. 



5. Remove to a fresh bath of spirit and watch care- 

 fully. When the natural co Jours show in their original 

 tints, average time three to six hours, remove the tis- 

 sues from the spirit bath, dry off the spirit from the 

 cut surfaces by mopping with a soft cloth, then transfer 

 to the mounting solution. 



Jore 's mounting solution (modified) consists of 



Glycerine 500 c.c. 



Distilled water 750 c.c. 



Formalin 2 c.c. 



