When measuring magnetic direction using a parallel rule, the edge passes through which part of the compass rose?

When measuring magnetic direction using a parallel rule, the edge passes through which part of the compass rose?

• A. Center of the compass rose and the bearing number on the inner ring
• B. Outer edge of the compass rose
• C. The North point of the compass rose
• D. The intersection of latitude and longitude lines

Answer: (A)

When you measure magnetic direction on a chart with a parallel rule, you align the edge so it passes through the center of the compass rose and through the bearing number on the inner ring. The center acts as the reference point for bearings on the chart, so a line drawn from the center along the edge defines the exact azimuth. The bearing number on the inner ring shows the specific magnetic direction in degrees, so placing the edge through that mark makes the line correspond precisely to that bearing. Using the outer edge wouldn’t align with the bearing scale, the North point is just a marker, and the intersection of latitude and longitude lines isn’t related to the bearing. This placement ensures the drawn line represents the intended magnetic direction on the chart.

When you measure magnetic direction on a chart with a parallel rule, you align the edge so it passes through the center of the compass rose and through the bearing number on the inner ring. The center acts as the reference point for bearings on the chart, so a line drawn from the center along the edge defines the exact azimuth. The bearing number on the inner ring shows the specific magnetic direction in degrees, so placing the edge through that mark makes the line correspond precisely to that bearing. Using the outer edge wouldn’t align with the bearing scale, the North point is just a marker, and the intersection of latitude and longitude lines isn’t related to the bearing. This placement ensures the drawn line represents the intended magnetic direction on the chart.