The brass bulb and brass boiler smoke stack were both shaped by the use of hand tools while spinning on a lathe.

黄铜灯泡和黄铜锅炉烟栈均形所使用的手工具，而纺纱对车床。

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The lower density means dramatically less drag force acting on the spinning disk stack so that mechanical power into the motor is substantially reduced.

ENGADGET: HGST develops helium-filled, high-capacity hard drives: no, they won't float away