方位儀; 羅經刻度盤; 啞羅經
Pelorus \Pe*lo"rus\, n. [After Pelorus, said to have been Hannibal's pilot when he left Italy.] (Navig.) An instrument similar to a mariner's compass, but without magnetic needles, and having two sight vanes by which bearings are taken, esp. such as cannot be taken by the compass.