to 10, 000 feet. Suspended matter, yet unanalyzed as to 

 animate and inanimate constituents, may contain many 

 forms too small to be recognized without optical magnifica- 

 tion. 



Sampling has been limited due to sampler failures. 

 However, prototype sampling devices are under develop- 

 ment and test (fig. 13-16). 



Biological entities and their remains appear to con- 

 stitute an important interference factor in the propagation 

 of sound through long deep-water paths. It is planned to 

 explore the effects of these organisms on sound propagation 

 using equipment carried aboard the TRIESTE. 



J 



Figure 13. Prototype multiple plankton sampler. Twenty 

 individual samples are selected 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 ambient- pressure- compen- 

 sated 6- or 12- volt dc motor- driven propeller located in 

 a stainless steel cover at the apex of the conical shroud. 

 Beneath the conical shroud is the prototype system wherein 

 a set of standard lead- acid batteries were compensated to 

 ambient pressure. 



46 



