SECTION TWO 



Ferric chloride (hydrated) io% 



aqueous . . . . . . 8 ml. 



Iodine solution (i gm. iodine, 2 



gm. KI, 50 ml. water) . . 8 ml. 



Note: Solution A deteriorates after twenty-four 

 hours. 



B. Ferric chloride hydrated 2% aqueous. 



C. Van Gieson stain. 



Tissues should be fixed in Zenker or in 10% formalin: if the 

 former is used mercurial precipitates are removed by the iodine in 

 the staining solution and it is not, therefore, necessary to treat the 

 sections or tissues with iodine before staining. 



Technique: 



Paraffin wax, Celloidin or L.V.N, may be used for embedding. 



1. Sections are brought down to distilled water; then im- 

 mersed in Solution A for one quarter to one hour until quite black. 



2. Differentiate for a few minutes in Solution B, controlling by 

 examination in water under the low-power objective. 



3. Wash with tap water; then immerse in 95% alcohol to 

 remove iodine. 



4. Wash in tap water for five minutes; then counterstain in 

 Van Gieson for three to five minutes. 



5. Differentiate in 95% alcohol; then dehydrate. 



6. Paraffin sections are cleared in xylol ; Celloidin or L.V.N, in 

 terpineol (after 95% alcohol). 



7. Mount in Cristalite or in balsam. 



Results: 



Elastic fibres, intense blue-black to black. Nuclei, blue to black. 

 Collagen, red. Other tissue elements, yellow. 



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