ClipArt ETC
"The inner circle incloses a map upon which the horizontal direction of the lower currents is shown by unbroken arrows, and that of the upper currents by broken arrows. The map is surrounded by a vertical section of the atmosphere in which the up-and-down are also shown by arrows. Near the equator the air rises and moves westward, and near the tropics it moves eastward and descends." -Dryer, 1901

Atmospheric Circulation

"The inner circle incloses a map upon which the horizontal direction of the lower currents is shown…