Rapid
A rapid is a section of a river where the river bed has a relatively steep gradient causing an increase in water velocity and turbulence. A rapid is a hydrological feature between a run (a smoothly flowing part of a stream) and a cascade. A rapid is characterised by the river becoming shallower and having some rocks exposed above the flow surface. As flowing water splashes over and around the rocks, air bubbles become mixed in with it and portions of the surface acquire a white colour, forming what is called "whitewater". Rapids occur where the bed material is highly resistant to the erosive power of the stream in comparison with the bed downstream of the rapids. Very young streams flowing across solid rock may be rapids for much of their length.
Read more about Rapid.
Famous quotes containing the word rapid:
“he dreadful darts
With rapid glide along the leaning line;
And, fixing in the wretch his cruel fangs”
—James Thomson (1700–1748)
“The art of watching has become mere skill at rapid apperception and understanding of continuously changing visual images. The younger generation has acquired this cinematic perception to an amazing degree.”
—Johan Huizinga (1872–1945)
“In a time of confusion and rapid change like the present, when terms are continually turning inside out and the names of things hardly keep their meaning from day to day, it’s not possible to write two honest paragraphs without stopping to take crossbearings on every one of the abstractions that were so well ranged in ornate marble niches in the minds of our fathers.”
—John Dos Passos (1896–1970)