上齿轮

The teeth on the gears mesh as they turn round.

转动时轮上与相啮合。

The statue of General Sedgwick, cast from cannons captured by the VI Corps which he commanded during the Civil War, has rowel spurs that turn.

塞吉维克塑像由一门他在内战中领导缴获大炮浇铸成，周围是马刺上轮。