362 CHAPTER XXX. 



a few seconds Jrops them face downwards into a solution 

 of— 



Absolute alcoliol saturated with eosin . 25 c.c. 

 Pure ether . . . . . 25 „ 



Sublimate in absolute alcohol (2 grms. 



to 10 c.c.) . ... 5 drops. 



Aftt'r three or four minutes they are washed^ stained^ and 

 mounted in balsam. 



For Jennee's fixing and staining and staining method, see 

 next §. 



Many recent authors fix wet films with formal. BiiNARio 

 [Deut. med. Wochenschr., 1895, p. 572) mixes 1 part of 10 per 

 cent, formol with 9 of alcohol (the mixture must be freshly 

 prepared), and plunges films into it for a minute. 



Similarly Gui.land, with 1 part of formol to 9 of alcohol. 



Similarly Weemel (see Zeit. wins. Mik., xvi, 1899, p. 50), 

 who combines various stains (methylen blue, eosin, gentian, 

 etc.) with the formol. 



Bdinqton {Brit. Med. Journ., 1900, p. 19) exposes films 

 for 15 to 30 minutes to vapour of formol under a bell-jar. 



Scott {Journ. of Path, and Bacter., vii, 1900, p. 131) 

 exposes films to the vapour for about 5 seconds and drops 

 into absolute alcohol, and after 15 minutes stains and mounts. 



A short exposure (30 seconds) to vapour of osmium has 

 also been recommended. 



720. Stains for Blood. — Fresh (unfixed) blood can be stained 

 on the slide. 



ToisON {Juvrn. Sci. med. de Lille, fev., 1885 ; Zeit. iviss. 

 Mik., 1885, p. 398) recommends that it be mixed with the 

 following fluid : 



Distilled water . . . 160 c.c. 



Glycerin (neutral, 30° Baume) 30 „ 



Pure sulphate of sodium . . 8 grammes. 



Pure chloride of sodium . . 1 gramme. 



Methyl violet 5 B . . 0-25 „ 



(The methyl violet is to be dissolved in the glycerin with 

 one half of the water added to it; the two salts are to be 

 dissolved in the other half of the water, and the two solu- 

 tions are to be mixed and filtered.) This mixture stains 

 leucocytes sharply, which facilitates enumeration. 



