

i ..."S i 





i 











pip 



^^^m 



*»8ffi mp^"*^ Sag 



















Figure A4. Leitz instantaneous capture horizontal suspended 

 sediment sampler end elevation (left) and side elevation (right) 

 (from Inter-Agency Committee on Water Resources 1940a) 



mixing of the collected sample with sediment from other 

 depths during descent and ascent of the sampler (unless 

 immediately closed) , non-uniform filling rate of the 

 sampler, and unsuitability for sampling in shallow streams 

 and near the river bed. Bottle samplers were used to 

 obtain sediment concentrations in the nearshore" zone of the 

 north New Jersey coast in the early 1930 's (Morrough P. 

 O'Brien, personal communication 1986). 



b. Integrating samplers . Integrating samplers collect a sample 

 over a period of time or through a depth. The quantity of 

 sediment is then averaged by the time period or distance to 

 obtain a representative sample. 



(1) Time- and depth- integrating samplers 



Time- and depth- integrating samplers consist of a container 

 such as a milk bottle with a valve so that air can escape 

 as the sample is being collected. The container is held in 

 a streamlined shell to weight the sampler and control its 

 horizontal attitude. Both laboratory and field tests have 

 been conducted for certain versions of these samplers to 

 ensure that the flow velocity at the sampling point is 



A8 





