-124 Journal of Applied Microscopy 



ing with eosin and methylen blue : Dry preparations are fixed in alcohol 

 and ether, stained for 30 seconds in a concentrated watery solution of eosin, 

 washed in distilled water and dried. They are then stained for about 30 seconds 

 in a concentrated watery solution of methylen blue, washed again, dried, and 

 mounted. 



Gabirtschcwsky (I SOI) also employed successive staining with eosin and 

 methylen blue for studying the so-called polychromatophile degeneration of red 

 blood corpuscles. Preparations dry heated or fixed in alcohol and ether were 

 stained five minutes in a solution of eosin (1 : 100 parts in (30 per cent, alcohol, 

 diluted one-half with distilled water before using), then washed in water and 

 counter-stained with a concentrated watery solution of methylen blue, which is 

 likewise diluted with an equal volume of water before using, for from one-half to 

 one minute. The preparation is then washed, air-dried, and mounted. Normal 

 erythrocytes stain red, polychromatophile erythrocytes blue red, leucocytes blue, 

 protoplasm red, acidophile granules intense purple, blood plates a mixed eosin 

 and methylen blue color. 



Canon (1892) employed a mixture in the following proportions for differ- 

 entiation of acidophile and mast cells : 



Concentrated watery solution of methylen blue, 40 grs. 

 One-half per cent, eosin solution in 70 per 



cent, alcohol, - - - - - - 20 " 



Distilled water, ------ 40 " 



Air-dried preparations were fixed at least five minutes in absolute alcohol. 

 The staining was done in a thermostat at 37° C. for from three to six hours. 



Canon and Pielicke (1892) used a mixture with less eosin in order to get 

 a stronger counter stain : 



Concentrated watery solution of methylen blue, - 40 

 One-quarter per cent, eosin solution in 70 per cent. 



alcohol, - - - - - - - 20 



Distilled water, ------ 46 



Mannaberg (1893) recommends the following procedure : Dry prepara- 

 tions fixed one-half hour in alcohol and ether are dried between filter paper and 

 floated one-half hour upon a half saturated solution of methylen blue, washed 

 in water, dried between blotting paper once more, then stained with a two per 

 cent, solution of eosin in 60 per cent, alcohol for another half hour, washed in 

 water, dried and mounted in xylo-Canada balsam. Both stains may be used 

 combined according to the following formula : 



Saturated watery solution of methylen blue, - - 40 

 Two per cent, eosin in 60 per cent, alcohol, - 80 

 Water, --------- 40 



Recently neutral combinations of eosin and methylen blue have become the 

 most important staining reagents in the study of the blood. These will be 

 considered in the section on neutral stains. 



5. Methyl Eosin and Gentian Violet. — Hlava (1883) used this double staining 

 for demonstrating blood plates. Preparations heated above a flame or fixed in 

 concentrated sublimate solution or in alcohol were first stained in a concentrated 

 watery solution of methyl eosin while warm, then shortly in 0.5 per cent, gentian 

 violet. He also stained with fuchsin and methylen blue. 

 Massachusetts State Board of Health. ErnesT L, WalKER. 



