IOO 



75 



5 



2 5 



C urve 



Curv 



r R< 



u 



sn 



fo A Resin 



\ 



es 



Cells 





7 



(D 



(*! 



FIG. 45. Curve showing the approximate development of resin passages 

 and the corresponding obliteration of resin cells 



147 



