PHYSICAL OCEANOGRAPHY OF THE GRAND BANKS AND 

 THE LABRADOR SEA IN 1955 ' 



By Floyd M. Soule and J. E. Murray 

 (U. S. Coast Guard) 



As in each of the seasons since 1948, in 1955 the JJSCGC Evergreeri 

 served as the oceanogTaphic vessel of the ice patrol. Descriptions of 

 the equipment in the laboratory and on deck for carrying out the 

 mission of ice patrol oceanography are to be found in earlier bulletins 

 of this series. The only change in 1955 was the addition of eci[uipment 

 for taking 40-gallon water samples from subsurface levels down to 

 depths of 150 meters. A continuous length of polyethelene plastic 

 pipe was joined to an axial brass pipe and this ended externally at a 

 packed slip joint where connection was made to a gear pump and 

 valving system which permitted priming of the pump and plastic 

 pipe with water from the ship's fire main. The plastic pipe was rove 

 through a light 30-inch diameter fairlead sheave and the intake end 

 lashed to the manila leader between the sinker and the ^32-inch wire 

 rope which is normally used for handling Nansen water bottles. A 

 bathythermograph was suspended from a bridle just below the sinker. 

 It was found necessary to control the plastic pipe by securing it to 

 the whe rope at intervals of about 1 5 meters as the pipe and wire were 

 paid out. This was accomplished by means of snap hooks lashed to 

 the pipe and snapped around the whe at points where clamps from 

 Nansen water bottles were clamped to the wire Priming was com- 

 pleted before submerging the intake end of the pipe. Once sub- 

 merged, pumping continued until all deshed levels were sampled. 

 At each sampling level, it was of course necessary to flush the pipe 

 and pump system before taking the sample Because of the friction 

 head involved the pumping rate was slow with %-inch pipe. Trials 

 of a l}^-inch diameter pipe resulted in little saving in time as the 

 increased pumping rate was overbalanced by the necessity of flushing 

 four times the volume of pipe. Buoyancy of the pipe was a considera- 

 tion and it was found that about 200 pounds of bronze sinkers were 

 necessary with the l}^-inch pipe. The method described was found 

 to be feasible in quiet water for depths down to about 150 meters.. 

 For deeper samples other methods of collection are more likely to be 

 productive. 



' To be reprinted as Contribution No. 801 in the Collected Reprints of the Woods H^le Oceanographlc 

 Institution. 



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