I300 



BULLETIN OF THE BUREAU OF FISHERIES. 



valve, the instrument may be locked in the set position, but it is automatically 

 unlocked when it is raised by the cord. 



As the instrument is lowered there is a free flow of water through the barrel, 

 so that at any given time its contents are taken from the stratum in which it 



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/0/7. 



Vw.. I. 



Water specimen cup. 



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Fig. 2. 



rests. When bottom is touched the tension on the cord is relaxed, the tripping 

 device instantly releases the upper valve and the barrel suspended from it, and 

 they fall into their respective seats, inclosing a sample of water before it can be 

 contaminated by the stirred-up bottom deposits. As the barrel is lo inches 



