Alidade, Navigational Tool

An alidade (archaic forms include alhidade, alhidad, alidad) is an instrument for taking bearings, consisting of two arms revolving around a circular brass plate or dial marked with points and degrees of the compass. It is secures on top of the binnacle hood and set to the ship's course, so that any bearing given by it will represent the magnetic bearing as by the compass beneath

Restrictions Only for Ireland and United Kingdom

Bearings Compass Degrees Dial Magnetic Navigational Points

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