MESSENGER— [jp 



MESSENGER 



G SPRING 



2 



SHUTTER ROD 

 A 



B FINGER LUGS 

 GATE LOCK 

 ARMS IN CAP 



SUPPORTING 

 CLAMP F 



MESSENGERS 



ROD FIXED TO TRIGGER 

 ARMS IN CAP C 



THE FIRST MESSENGER TRIPPED THE TRIGGER FOR THE 

 FIRSTTIME. THE FIRST MESSENGER OFTHE SECOND SET 

 BELOW THE INSTRUMENT HAS BEEN CAST OFF. 



Figure 8-2. Side view of Clarke-Bumpus plankton sampler. 



the rod (D) from the trigger engages the 

 second of the horizontal arms (C) . The tension 

 of the springs may be increased by removing 

 the stops and giving the shafts extra turns in 

 the direction opposite to their operation. The 

 shutter has now been brought into the cocked 

 closed position ; the sampler is ready for attach- 

 ment to the cable. 



H. O. 607 



Another important advantage of the Clarke- 

 Bumpus sampler is that it can be used in series 

 on the same wire; hence, quantitative vertical 

 tows can be made. In case more than 1 sampler 

 is to be used, 2 messengers must be hung from 

 the hooks at the base of rod (A) when the 

 shutter is set. It is necessary that the wire of 1 

 messenger be about 10 inches long; the loop 



81 



