plumb bob

基本解释

If you have a good eyeball you can do it that way or use a plumb bob .
如果你有一个良好的眼球，您可以这样做或使用一个铅垂鲍勃。
The gyroscopic surveying instrument uses a gyroscope, compass card, plumb bob, and modified movie camera.
陀螺测量仪由陀螺仪、罗盘、铅锤以及经过改造的电影摄像机等组成。
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Innage measurement is taken by lowering the steel tape with plumb-bob attached into the liquid until the plumb-bob touches the bottom of the tank or the gauge or datum plate.
实高量油时，将带铅锤的量油尺放入液体内并一直将尺下放至铅锤接触罐底、或接触计量基准板。
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Other important construction tools include the plumb bob, the wrench, the rope and the chain.
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