| 摘要 |
A string of parallel oyster trays (1) are buoyantly supported by floats (4) at each end. These floats and the associated trays are attached to parallel wires secured at their ends (3) so that they are at the surface level of water in which the trays are buoyantly supported by the floats. The floats are moveable between stable positions at which the trays are pendently supported between them so that the oysters are carried just beneath the water surface and stable, positions at which the floats locate beneath opposite-end portions of the trays. The buoyancy of the floats when in the latter positions is such that the oysters in the trays are held slightly above the level of the water surface. Movement of the floats between their two stable positions is carried by arrangements supported by a punt which is driven alongside the string of trays when the floats are to be moved between their two positions.
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