SECTION TWO 



D. Brown gold chloride . . . . 0-2 gm. 



Distilled water . . . . . . 100 ml. 



Glacial acetic acid . . . . i ml. 



Note: Solutions A, B, C and D must be stored in 

 dark bottles. 



E. Oxalic acid 2% aqueous. 



F. Sodium thiosulphite 5% aqueous. 



G. Gallocyanin solution (Einarson). 



H. Phosphotungstic acid 5% aqueous. 



I. Aniline Blue 1% aqueous 

 Fast Green FCF . . 

 Orange G 

 Glacial acetic acid 

 Distilled water 



Note: This solution should be diluted 2 : 3 with 

 distilled water before use. 



Technique: 



Note: Metallic instruments must not be used in the following 

 procedures which should be carried out in a darkened room. 

 Sections should be stained in black embryo dishes or in tubes 

 covered all round with thick brown or black paper. 



Fix in 10% formalin and embed in Celloidin or L.V.N. Sec- 

 tions are cut 15 to 25^ in thickness. 



1. Immerse for twenty-four hours in ammoniated alcohol 

 (cone, ammonia i ml., alcohol 50% 99 ml.). 



2. Drain well and transfer to Solution A for six to eight hours 

 at 37° C. 



3. Drain well and transfer to Solution B in another staining 

 dish, for twenty-four to forty-eight hours at 37° C. 



4. Rinse for about five to ten seconds in 50% alcohol; then 

 reduce with Solution C for about ten minutes. 



5. Wash in several changes of distilled water; then tone in 

 Solution D for ten minutes. 



6. Wash in several changes of distilled water ; then transfer for one 

 to three minutes in Solution E, afterwards rinsing in distilled water. 



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