STAINING, PRACTICAL AND THEORETICAL 



(b) Steps 1-4 constitute the Falg reaction (as page 198). 

 The acid bath (step 5) curbs the decolorizing effects or orange G 

 so that the strongly erythrophile elements remain stained (red). 



(c) The picture obtained with the Falgog method (or the 

 Falgose, described below) is superior to that produced by 

 simple staining with acid fuchsin. Probably the orange G and 

 glucose combine with and decolorize (reduce) definite falg-tissue 

 compounds (chemical), thereby producing sharper pictures of 

 the erythrophile elements. 



(d) While the Falgose method is recommended for the 

 usual microscopic sections (i.e. up to a thickness of loo/x) the 

 Falgog method is preferable for thicker sections (over 100^), 

 including thick pieces of tissue (e.g. omentum). The reason for 

 this is that the stronger Orange G solution used in the Falgog 

 method tends to stain many tissues. In thick sections the stronger 

 Orange G is apparently necessary to ensure the removal of colour 

 from moderately and weakly erythrophile elements. Instead of 

 being entirely removed the violet colour may be reduced to a 

 faint blue or green. This, however, has no effect on the clarity 

 of the picture of the blood vessels, and may in fact be useful. 



(e) Reference should be made to pages 76-90 of this book and 

 to the authors' original papers for an explanation of the mechanism 

 of the staining reactions, and for other information. 



FALGOSE METHOD 



For demonstrating erythrocytes, minute blood vessels, 

 and other strongly erythrophile elements of animal and 



plant tissues 



Solutions required: 

 As in the Falgog method, plus the following: 



E. Glucose, anhydrous . . . . i gm. 

 Water 100 ml. 



F. Equal volumes of solution D 



(Orange G) and E 



Technique: 



Exactly as in the Falgog method except solution F (above) 

 is used in place of solution D, 



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