Page:A Treatise on Geology, volume 2.djvu/39

 CHAP. VI. , tends to fall from the surface of the water, as it moves forward, or to the right and left of the point of entry of the river, and with an accelerated velocity in the lower part. The path of each particle will be more or less influenced by the direct, lateral, or vertical forces, according to its magnitude and weight. Thus, in the diagram No. 77., which is to represent a vertical section along the path of the river as it enters the lake at the point o, P p p, particles of unequal magnitude, entering together, describe curves of unequal curvature (they are all related to the same vertical axis, G); the smallest particles being transported furthest, because they have, proportionally, the largest surface, and therefore subside most slowly in the water.

On the horizontal plan (No. 78.) the courses of such deposits are shown to be concentrical, or nearly so, to the point of influx of the river. By such deposits, the Delta of the Rhone in the Lake of Geneva, as well as that of the Derwent in the Lake of Keswick, has been

Delta