§ 23072 Directional Terms Defined

• •Words like 'northerly' mean straight north unless something else says different.
• •If a map or a river shows a different direction, follow that instead.
• •This rule helps people understand directions the same way.

You're reading a map that says 'go northerly' but there's a river bending to the left.

Follow the river's direction instead of going straight north because the river is a natural object that changes the meaning.