Eddies
In fluid dynamics, an eddy is the swirling of a fluid and the reverse current created when the fluid flows past an obstacle. The moving fluid creates a space devoid of downstream-flowing fluid on the downstream side of the object. Fluid behind the obstacle flows into the void creating a swirl of fluid on each edge of the obstacle, followed by a short reverse flow of fluid behind the obstacle flowing upstream, toward the back of the obstacle. This phenomenon is most visible behind large emergent rocks in swift-flowing rivers.
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Famous quotes containing the word eddies:
“Well, Pa, a woman can change better than a man. A man lives, sort of, well, in jerks. A baby’s born or somebody dies and that’s a jerk. He gets a farm or loses it and that’s a jerk. With a woman, it’s all in one flow, like a stream. Little eddies and waterfalls, but the river, it goes right on. A woman looks at it that way.”
—Nunnally Johnson (1897–1977)
“The elaborate star-light throws a reflection
On the dark stream,
Till all the eddies gleam;
And thereupon there comes that scream
From terrified, invisible beast or bird:
Image of poignant recollection.”
—William Butler Yeats (1865–1939)
“There sighs, lamentations and loud wailings resounded through the starless air, so that at first it made me weep; strange tongues, horrible language, words of pain, tones of anger, voices loud and hoarse, and with these the sound of hands, made a tumult which is whirling through that air forever dark, as sand eddies in a whirlwind.”
—Dante Alighieri (1265–1321)