FIXING AND HARDENING AGENTS. 55 



it is the glacial acid that is meant unless the contrary is 

 stated. 



All liquids containing a large proportion of this acid (e. g. 

 ^ 85, 86) should only be allowed to act for a very short 

 time. 



85. Acetic Alcohol (CARNOY, La Cellule, iii, 1886, p. 6; and 

 ibid., 1887, p. 276; v. BENEDEN et NEYT, Bull. Ac. Sci. Belg., 

 xiv, 1887, p. 218 ; ZACHARIAS, Anat. Am., iii, 1888, pp. 

 24 27; v. GEHUCHTEN, ibid., 8, p. 227). CARNOY has given 

 two formulas for this important reagent. The first is 

 Glacial acetic acid . . .1 part. 



Absolute alcohol . . .3 parts. 



The second is 



Glacial acetic acid . . .1 part. 



Absolute alcohol . . .6 parts. 



Chloroform . . . . 3 



The addition of chloroform is said to render the action of 

 the mixture more rapid. 



V. BENEDEN and NEYT take equal volumes of glacial acid 

 and absolute alcohol. 

 ZACHARIAS takes 



Glacial acetic acid . . .1 part. 



Absolute alcohol . . .4 parts. 



Osmic acid . . . .a few drops. 



Acetic alcohol is one of the most penetrating and quickly 

 acting fixatives known. It preserves both nuclei and cyto- 

 plasm, and admits of staining in any way that may be 

 preferred. It was employed by all of the authors quoted 

 for the ova of Ascaris proverbially one of the most difficult 

 objects to fix, but I have found that it is applicable to 

 many other objects. Wash out with alcohol, and avoid 

 aqueous liquids as far as possible in the after-treatment. 



86. Acetic Alcohol with Sublimate. CARNOY and LEBRUN (La 

 Cellule, xiii, 1, 1887, p. 68, due to GILSON). 



Absolute alcohol . . . .1 vol. 



Glacial acetic acid . . 1 



Chloroform . . . . 1 



Sublimate to saturation, 



