Dividers
Dividers are used to measure distance on the chart. Open them to span the distance you want to measure, then transfer them to the latitude scale at the side of the chart (at approximately the same latitude). Read off the distance in nautical miles.
For long distances, set the dividers to a convenient span (e.g., 5 nautical miles using the latitude scale), then 'walk' them along the route, counting the spans. Add any remaining partial span.
Key Points
- Measure distance on the LATITUDE scale (side of chart)
- Use at approximately the same latitude as your measurement
- For long distances: set to a known span and walk along the route
- One minute of latitude = one nautical mile
Tip: When using dividers on a bouncing boat, press the points gently into the chart so they don't slip. A light dimple won't damage the chart.