9. Put the friction cap back on the bucket 

 and put the bucket back on funnel A. 



10. When the timer rings again, switch the 

 valve back to funnel A, record the water- 

 meter reading and remove the sample from 

 funnel B as above. 



11. Repeat the procedure to the end of the 

 sampling sequence, at which point the timer 

 can be switched off and the water diverted 

 to the scuppers of the vessel. 



This procedure generally requires 2 or 3 

 minutes work each time a sample is taken, 

 leaving a few minutes for the operator to take 



care of odd chores, such as making notations 

 on the temperature recorder and preparing 

 labels for the sample jars. 



The spray gun referred to in step 7 was 

 found to be very effective in removing the 

 sample from the bucket. Actually the bulk 

 of the plankton is first removed by tipping 

 the bucket over a small powder funnel set 

 in the sample jar and washing the inside 

 down with a gentle stream of water from a 

 small hose connected to a laboratory tap. 

 Organisms remaining on the screen are re- 

 moved by placing the bucket upside down in 

 the powder funnel (fig. 11) and "blasting" 



Figure ll.--The collecting bucket being cleaned with the spray gun. 



12 



