A direct thermally driven and zonally symmetric circulation under the strong influence of the earth's rotation, first proposed by George Hadley in1735 as an explanation for the trade winds. It consists of the equatorward movement of the trade winds between about latitude 30° and the equator in each hemisphere, with rising wind components near the equator, poleward flow aloft, and, finally, descending components at about latitude 30° again. In a dishpan experiment, a Hadley cell is any direct thermally driven vertical cell of the approximate scale of the dishpan.