REACTIONS OF FIXATIVES WITH TISSUES AND CELLS 87 



the dimensions of the piece of tissue, the weight appHed at the free 

 end, and the amount of sag. The higher the coefficient, the more 

 rigid the tissue. Unfortunately he made only one or two obser\^a- 



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FIG. 13. Diagram showing the coefficient of elasticity of the belly- 

 muscle of the cat, fixed in various ways. The black columns show 

 the coefficient after fixation, the white columns after fixation and 

 subsequent soaking for 4 days in 8o°o ethanol. 

 (From the data of Wetzel. "=) 



tions with each fixative. Sometimes he transferred the tissue from 

 the fixative to 80% ethanol and measured the elasticity once more. 

 Some of his results are reproduced graphically in fig. 13. The 

 excessive hardening effect of acetone and ethanol will be noticed. 

 No other fixative approaches these two. Potassium dichromate, 



