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Show 478 " As the volume of flow crosses from the right bank to the left, if it crosses in a concentrated stream, it will dig out a fairly deep channel, a channel comparable to what you find at other points on the river. " If, on other hand, it spills over gradually, there is no assurance that there will be any water anywhere across such a bar. " Another case is when the up stream deep channel cuts off quite shortly. In other words, shortly after leaving the right bank, -- shortly after leaving the curve which is curving to the left, the deep water may terminate and the river may cut across to the opposite or left bank. [ R. 1222] " Still other cases, the channel from the lower bend which is curving to the right, the channel following the left bank of the river may extend only a short distance, or possibly no distance at all above the bend. " In such an instance we have a long shoal, depending upon the length of the straight reach, and the channel may be most anywhere in that area. " The problem in navigation is that wherever the river changes curvature, it is necessary to change the course of the boat from one bank to the other, and in making that change it is necessary to, in general, cross a high stage bar which has been more or less cut out during the falling stages, and which may or may not have a good channel across it. " Q How, what you have just said applies to the |