A measuring instrument used with the magnetic compass. For obtaining the azimuth of observed objects by observing an object’s reflection in a mirror or prism, pivoted in the centre of glass over a compass card.
与磁罗盘一起使用的测量仪器。通过观察物体在镜子或棱镜中的反射来获得被观测物体的方位,在罗盘卡片上的玻璃中心枢转。