David Potasznik, age 9, of East Brunswick, N. J., for his question;

What is a meridian?

The streets of a town help us to find. Our way around. A trip to the post Office may be six blocks north and two blocks east. Long ago, some Vise men divided our whole globe into blocks to help travelers find their way around the earth. The blocks are divided with imaginary lines. One of the main divisions is the equator that runs around the wide waist of the world.

From the equator to each pole, the side to side guiding lines are called lines of latitude. They show the east and west directions. The lines of longitude run from pole to Pole and show the north and south directions. These up and down lines were once called meridians. We may still call them meridians, but they are also the lines of longitude that run from Pole to pole, slicing the globe into orange sections.