Figure 14. Another prototype multiple plank- 

 ton sampler. Ten individual samples are se- 

 lected on command by remote control and held 

 in storage under sea water until removed for 

 analysis or preservation. Water is pumped 

 through standard plankton netting by an ambi- 

 ent-pressure-compensated 24-volt dc motor- 

 driven propeller located in a stainless steel 

 cover below the acrylic plastic sampling unit. 

 An ambient pressure compensated solenoid, 

 located upper left, is used to release sampling 

 discs into the storage position. Additional 

 sampling units can be easily added to the 

 "stack" of ten shown. 



Figure 15. End-on view of sampler of 

 figure 14. Polyethylene bottles serve as 

 reservoirs for the electrically non-conducting 

 fluids used to compensate for ambient sea pres- 

 sure and to prohibit the entry of sea water into 

 the electrical circuits. This sampler was 

 successfully operated to depths of 18, 900 feet. 

 Power for the motor was taken from the pro- 

 totype system used for operating standard 

 lead-acid batteries at ambient hydrostatic 

 pressures. 



47 



