Longitude is basically a way of breaking the sphere into 360 degrees. However ... That's where the protractor comes in play. Here's what you do. Take a string with a weight to act as a plumb ...

A protractor acts in a similar way to a ruler ... semi-circular (0-180 degrees - pictured above ) and a circular (0-360 degrees - pictured right) . They often have two sets of numbers going ...

A protractor acts in a similar way to a ruler ... semi-circular (0-180 degrees - pictured above ) and a circular (0-360 degrees - pictured right) . They often have two sets of numbers going ...