Figure 21o — Apparatus used in testing the effect of carbonized 

 sand and oil mixture on oysters » 



Upper level: On the left, timing device consisting of 



teleorOTie motor and disc making an electric contact 

 every 30 minutes. On the right, constant level tanks 

 (2) from which sea water is supplied to the mixing 

 chambers. 



Center: Two kymographs which record on smoked drum the 

 muscular activity (upper line); rate of pumping 

 (second line); and time interval (third line). 



Lower level: Two dumping vessels (standing in large white 

 tank) for recording the amount of water pumped by the 

 oyster. Mixing chamber (6) is seen on the extreme 

 right. It supplies water to the constant level tank 

 (1) in which the oyster is kept* 



