Chart Navigation & Plotting · Position — Plotting Latitude and Longitude
When plotting a position by latitude and longitude on a Mercator chart, you should:
- AMeasure both from the compass rose
- BMeasure latitude on the side (latitude) scale and longitude on the top/bottom (longitude) scale at the position✓ Correct
- CMeasure latitude on the top scale and longitude on the side scale
- DUse dividers set to the chart's stated scale ratio
Explanation
Latitude is read from the side (vertical) borders and longitude from the top/bottom (horizontal) borders. Step off the latitude from the nearest parallel and the longitude from the nearest meridian to fix the position precisely.
Authority: Bowditch (Pub. No. 9), plotting positions
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