SECTION ONE 



Technique: 



Fix for six to twenty-four hours; then wash in running water 

 for the same length of time. 



Flemming's Fluid (Strong) 



Recommended for : 



Plant and animal tissues, for cytological detail; for cellular 

 structures; and for fat. 



Formula: 



A. Chromic acid I % .. .. 30 ml. 

 Acetic acid, glacial . . . . 2 ml. 



B. Osmic acid 2% . . . . . . 8 ml. 



Mix A and B immediately before use. 



Technique: 



Fix for one to twenty-four hours according to the material ; for 

 chromosomes an hour is sufficient. Wash with running water for 

 twenty-four hours. 



Remarks: 



The penetration power of this fixative is poor ; and that of the 

 weak solution {see below) is poorer still; however, either solution 

 gives good results with basic stains, particularly safranin, and iron 

 haematoxylin. Quite apart from their high cost, Flemming fixa- 

 tives should definitely not be employed as general fixatives, but 

 only in special cases for very small pieces of tissue where fixation 

 extending through a layer of about four or five cells in thickness is 

 sufficient, as this is the limit of their penetrating power even in 

 loose-celled tissues. 



Flemming's Solution (weak) 

 Recommended for : 



All purposes for which Flemming's strong solution is used. 



Formula: 



A. Chromic acid 1% . . . • 25 ml. 

 Acetic acid 1% . . . . . . 10 ml. 



B. Osmic acid 1% . . . . . . 10 ml. 



Distilled water . . . . • . 50 ml. 



