Similar to 磁気偏角
方位磁針
Compass▼-2 trends0
01
1▼-1 trends2
23
34
45
56
67
78
89
910
1011
11 (number)12
12 (number)13
13 (number)19
19 (number)40
40 (number)70
70 (number)100
100400
400 (number)700
700 (number)1000
1000 (number)1000000
1,000,000航海計器
象限儀
Quadrant (instrument)土圭
八分儀
Octant (instrument)バック・スタッフ
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