ADS 12.2-ADS 21.1 ACCESSORY DYE-STAINING SOLUTIONS 519 



12.2 Shunk 1920 11056,5:181 



formula: water 100, tannic acid 200, ferric chloride 1.25 



12.2 Stockwell 1934 19938,80:121 



formula: water 90, chromic acid 1, potassium dichromate 1, acetic acid 10 

 RECOMMENDED FOR: As a mordant prior to safranin staining, particularly for plant 

 tissues containing much phlobaphene. 



12.2 Trenkmann 1890 23684, 8 :385 



formula: water 100, tannic acid 2, hydrochloric acid 0.2 



12.2 Weiss 1929 ' 11284,14:1191 



formula: 95% ale. 65, tannic acid 65, 40% formaldehyde 32.5, acetic acid 2.5 



12.2 Winge 1930 23639b, 10 :699 



formula: 96% ale. 80, water 20, iodine 1, potassium iodide 1 



12.2 Yokata 1924 6630,90:1303 



formula: water 100, tannic acid 5, potassium antimony tartrate 0.5 



12.2 Zikes 1930 23684, 81 :161 



formula: water 116, tannic acid 15, chrome alum 9, osmic acid 0.112, crystal violet 0.15 

 preparation: Dissolve the tannic acid in 60 water. Add alum, dissolved in 37.5 and 

 osmic acid dissolved in 11.25. Filter. Add dye dissolved in 7.5. 



ADS 20 Differentiating Solutions 



The principal reason for separating these differentiating solutions from the stains 

 with w^hich they are used is that the same formula may be used with thirty or forty 

 stains, and will therefore have either to be given thirty or forty times in the section on 

 dye staining, or, alternatively, be the subject of continual cross references within the 

 section on dye staining. 



It is hoped that the technician will not hesitate to experiment by applying solutions, 

 designed for differentiating one particular technique, to quite different techniques. As 

 an example, one may quite the formula of Pal 1887 below, the use of which is generally 

 confined to the differentiation of hematoxylin-stained sections of nervous tissue. The 

 author recommends its employment, in another place in this book, for the surface 

 bleaching of parasitic flatworms which have been stained in carmine. Many other 

 examples of this kind of double use could be given and the whole science of microtomy 

 would greatly benefit were persons to experiment more widely with existing solutions, 

 rather than to invent new ones every time they are faced with new problems. 



Hematoxylin stains are usually differentiated with "acid alcohol" which is either 

 0.1% (British and American practice) or 1% (German practice) hydrochloric acid in 

 70% alcohol. 



The "glyceric ether," used in continental Europe for the differentiation of thiazin 

 stains, is not an article of commerce in the United States. It is prepared by the distil- 

 lation of glycerol over aluminum chloride at room temperature. The distillate, in micro- 

 tomic practice, is diluted with 10% glycerol in 95% alcohol according to the fancy of 

 the supplier or user. 



21 FOR DIFFERENTIATING HEMATOXYLIN 

 21.1 Formulas 



.21.1 Eisath 1911 14370, 20:3 



formula: water 55, 95% ale. 45, tannin 12, pyrogallic acid 6 



21.1 Gordon 1936 11284,22:294 



formula: water 90, 40% formaldehyde 10, ferric alum 0.25 



