Meaning of piston core sampler in English:
piston core sampler
noun
An underwater core sampler consisting of a long weighted cylinder containing at its lower end a piston attached to the lowering cable, devised so that when the cylinder enters the bottom sediments under its own weight the descent of the piston is arrested, and the resulting partial vacuum inside the cylinder causes the pressure of the water to force it further into the sediment.
Origin
1940s.
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