In Shelley's "Ode to the West Wind," the wind is an agent of change, a "wild spirit," both "destroyer and preserver." When Shelley writes that the leaves from the wind "Are driven, like ghosts from an enchanter fleeing, / Yellow, and black, and pale, and hectic red, / Pestilence-stricken multitudes," he means, of course, that the wind blows the dead leaves before it, but his language invests this simple action with a kind of dread significance: The wind is an "enchanter" from which the leaves flee like "ghosts." Similarly, the wind causes the clouds to fly "like earth's decaying leaves" across the sky. When he writes that the clouds are "Like the bright hair uplifted from the head / Of some fierce Maenad, / even from the dim verge / Of the horizon to the zenith’s height / The locks of the approaching storm," he means that the wind has has made the clouds of the approaching storm into the hair of a "Maenad," or a frenzied female worshipper of Bacchus, the god of wine. We can see that from the way Shelley describes the effect of the wind on the clouds and leaves that the wind is a spirit of wild, anarchic freedom, one which the poet longs to follow.