mdcreation 8" Vintage Navigation Straight Pattern Artist Drawing Brass Divider Drafting Kit  (Pack of 1)

Measuring the distance between two points on a chart is made easier with dividers. The dividers allow you to measure distance in nautical miles when used in conjunction with the latitude scale of your nautical map. Place one point of the dividers at point A and the other point of the dividers at point B. Keeping the same spread measure the distance on the latitude scale. If it’s 20 minutes of latitude, then the distance is 20 nautical miles, i.e. one minute is one nautical mile. Remember to only ever measure by latitude because longitude is different depending how far north or south you are. For measuring distances that are longer than your dividers, set the dividers to a whole number then rotate the dividers end to end and then add up the number of rotations.