CANYON (Anglicized

See also:

• FORM (Lat. forma)

form of Span.

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• CANON

canon, a

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• TUBE (Lat. tuba)

tube,

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• PIPE

pipe or

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• CANNON (a word common to Romance languages, from the Lat. canna, a reed, tube, with the addition of the augmentative termination -on, -one)

cannon; the

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• SPANISH

Spanish form being also frequently written)  , a type of valley with huge precipitous sides, such as the Grand Canyons of the Colorado and the Yellowstone rivers, and the gorge of the Niagara river below the falls, due to rapid stream erosion in a " young " land . A river saws its channel vertically down-wards, and a swift stream erodes chiefly at the bottom . In rainy regions the valleys thus formed are widened out by slope-wash and the resultant valley-slopes are gentle, but in arid regions there is very little side-extension of the valleys and the river cuts its way downwards, leaving almost vertical cliffs above the stream . If the stream be swift as in the western plateau of North America, the cutting action will be rapid . The ideal conditions for developing a canyon are: great altitude and slope causing swift streams, arid conditions with absence of side-wash, and hard rock horizontally bedded which will hold the walls up . A B C D .