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Show Record can count quite confidently on finding deep water as soon as the bend begin. It also happens on many occasions that that deep water will extend far up along the left bank of the river. Under such conditions the crossing bar frequently has a diagonal position 1222 This bar will ordinarily be built up during any freshet. It will occupy the same general position each year, but its form may be entirely different from year to year. As the volume of flow crosses from the right bank to the left, if it crosses in a con-centrated stream, it will dig out a fairly deep channel, a channel comparable to what you find at other points on the river. What I have said applies to the Colorado River as I saw it. You do not always have the channel in the same place on these crossing bars at the same volume of water. Ordinarily a change in the stage of the river causes a rearrangement of the bars; in other words, the bars are constantly changing, even though the stage is not changed, but that change is ordinarily comparatively slow in the low stages of the river. I made two separate trips, the first beginning at Moab and going down to just above the first cataract in Cataract Canyon on the Colorado River, the going up the Green River for a distance of five miles, then retracing the trip to Moab, Utah. On that trip 1226 Virgil Baldwin as boatman and Cecil Thompson as assistant boatman. With reference to the permanency of the bed of the Colorado River, I found that the river is quite permanently located between rock banks. It has very small opportunity to move sideways more than a few hundred feet. There are very few sections of the country where the river could move its full width without encountering the 1227 rock on the other side. With those rock limits, the bed of the Colorado River is exceedingly changeable. The bars along the side of the river had small trees on them about 20 years of age with a few exceptions. On my first trip I left Moab on August 25, 1929, quite early in the morning. On that day I got the stream flow unofficially 1229 by telephone from the station at Cisco as 6000 cubic feet per second |