Simple Mechanical Aid to Limnological Sampling

Abstract

( I Y" stainless steel bolts and nuts can be used instead of brass.To attach these water samplers to the hydrographic wire, specially designed attachment and release assemblies were made for us by the Hytech Corporation.2 These units consist of two cadmium plated irradiated brass castings provided with knurled stainless steel knobs, which tighten directly on the cable. This clamp can be used with any hydrographic cable between 3/32-and 7/32-in. diameter. A stainless steel %-in. tripping rod with cadmium plated button and "U" liead comprises the release assembly. This rod is 9 in. long from center to center of the clamp castings. The lower clamp assembly was used for both the release of the messenger as well as the wires for the closing valves. These attachment units provide stability on longer bottles and aid in supporting the weight of larger samplers. Two aeroseal _' Hytech Corporation, 6803 \\'clst Boule\xrd, Inglewood 3, California.stainless steel hose clamps were used to fasten the attachment and release units to the samplers. For rack storage a handle was riveted to the upper aeroseal clamp.These sample bottles are inexpensive to construct and permit multiple water samples to be made on one hydrographic cast. They are especially suitable for shallow water operation, where incomplete flushing of Nansen or similar water samplers mayoccur. Furthermore, the large capacity of the unit provides ample water for chemical and biological analysis.