SECTION TWO 



C. Iodine crystals, A.R. . . . . i gm. 

 Potassium iodide, A.R. . . . . 2 gm. 

 Distilled water . . . . . . 100 ml. 



Dissolve the potassium iodide in about 5 ml. of 

 distilled water, then shake in the iodine until dis- 

 solved ; add the rest of the distilled water and shake 

 thoroughly. 



D. Basic fuchsin . . . . . . 10 gm. 



Absolute alcohol . . . . 100 ml. 



Place in a 250 ml. flask and plug the neck with 

 non-absorbent cotton wool. 



Heat on a water bath to boiling point. 



Allow to cool to room temperature; then filter. 



E. Solution D . . . . • • 5 ml. 



Absolute alcohol . . • • 65 ml. 



Distilled water . . . . . . 30 ml. 



Paraldehyde . . . . . . 0-75 ml. 



HCl, cone. .. .. .. I -25 ml. 



Solution E can be prepared in the stoppered 

 bottle in which it is to be stored. After mixing, the 

 solution should be left to stand for three days at 

 room temperature by which time the reaction will 

 have been completed and the red colour of the 

 fuchsin will have disappeared, marking the comple- 

 tion of the reaction. Alternatively, the reaction 

 takes place in twenty-six hours if the solution is 

 kept at 37° C in an incubator. 



F. Periodic acid . . . . . . i gm. 



Distilled water . . . . . . 100 ml. 



G. Sensitized Schijf reagent 

 Hydrochloric acid N/i . . . . 20 ml. 



Distilled water . . . . . . 80 ml. 



Basic fuchsin . . . . . . i gm. 



Sodium metabisulphite . . . . 2 gm. 



(i) Shake in a closed bottle or stoppered flask at intervals 

 over a period of fifteen to twenty minutes until the colour of 

 the solution is pale yellow. 



(ii) Add 1-2 gm. of decolorizing charcoal; shake well; 

 then filter: the filtrate should be colourless. 



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