216 



The apparatus and plan of the experiment was practically the same 

 as in my former work. Tlie ])nuip was a Ducretet compression pump fitted 

 with a gauge recording pressure up to l.OOf) kilograms per S(iuare centi- 

 meter. The cell is made in llic // foi-ni with vci-y short connecting tuhe 

 (Fig. I), so that it will go inside the piezometer (I"Mg. 11), whose inside 



Fig. 11. 



F S 



FiK III. 



