| OCR Text |
Show and sediment . As Howard 136 points out Abs . R . , . vol . 2 , p . 970 ) , there is a continuous change ( taking taking- taking ) place in the beds of rivers having sandy beds . In the cataract section of the Colorado ( velocities' velocities velocities ) are apparently such that the only sediment in ( the the- the ) river bed consists of large boulders . It is a ( well-known wellknown ) scientific fact that ( flowing flowing- flowing ) water is capable of moving sediment ranging in size from the finest d6bris to large boulders . The method of movement varies ; fine material is ( car- car ) ried in suspension ; ( medium-sized mediumsized ) material slides ( or- or ) makes short skips , the larger rocks and ( boulders boulders- boulders ) roll . ( Howard and Love , Abs . R . , vol . 2 , p . 970 . ) On the Colorado and San Juan Rivers the movement of sediment may take place in the form of waves . The character and amount of material which ( will will' will ) move depend primarily upon the velocity , the size , and amount of the sediment , and , to a limited extent , upon the shape of the channel . ( Howard , Abs . R . , , vol . 2 , p . 970 . ) It is clearly evident that the Green , Colorado , and San Juan Rivers can not have stable or ( perma perma- perma ) ¬ nent channels since their beds are composed of sand , silt , and sediment of varying degrees of ( fine- fine ) ness and channel velocities range from 1 or 2 miles . an hour to over 10 miles an hour . Scientific ( deduc deduc- deduc ) ¬ tion leads to this conclusion . The conclusion is supported by actual observations , technical and . otherwise , as follows : |
