INTRODUCTION TO FIXATION 



23 



whether they he approximately on a straight line. This is so with 

 nearly all fixatives. (See, for example, fig. 3.) 

 Where the straight line crosses the ordinate line, log / has 



0-2 



0-2 0-4 0-6 0-3 



1-0 1-2 

 Log t 



1-4 1-6 1-a 2-0 22 



Fig. 3. Graph showing the rate of penetration of mercuric chloride 

 (at standard concentration) into gelatine-albumin gel. t is time in 

 hours; d is the distance penetrated in mm.'^^' '* 



become zero and log d = log K. One can therefore read off the 

 value of log K on the ordinate line, and the antilogarithm of the 

 figure obtained is therefore K. In the case of mercuric chloride 



