Beth Piper, age 11, of Costa Mesa, California, for her question:

How long have we had latitudes and longitudes?

Thousands of years ago, scholars thought of charting the earth in circles. Many wise men of the ancient world assumed that the earth is a globe and mapping it with circles seemed logical. The astronomers of ancient Babylon used lots of circles to chart the skies. And they coped with a circle by dividing it into 360 equal degrees. Pythagoras and other mathematicians of ancient Greece borrowed this system. So did Eratosthenes who was perhaps the first person to measure around the globe. He borrowed the latitude and longitude system from earlier scholars. This was around 100 B.C. These early scholars had latitudes and longitudes to chart the entire globe, though most of them never traveled far from home.

The ancient system of lines was somewhat neglected until the 17th century. In 1669, geographers first began using telescopes to line up the latitudes and longitudes precisely. Newton used these charts in his work. Hence, although the system was invented thousands of years ago, mankind began making the best use of it ;only about 300 years ago.