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 toward the island, which is thereby curtailed in its lower parts, and at its extremity contracted almost to a point. The two currents unite below, and form a deep channel. At the head of the island the water is shallow. The largest and oldest timber stands on the lower end, and {134} younger plants of willow, sycamore, &c. on the upper end of the island. It is farther to be noticed, that the trees on islands, although of rapid growth, are by no means so large as those on the adjoining banks and bottom lands. The alluvial process deposits gravel at the head. Over this, sand is precipitated; and lastly, a superstratum of mud and driftwood is deposited, forming a rich soil for the growth of timber. These facts, taken in connection, show that additions are continually making at the head, and that the converging streams are simultaneously carrying off the lower end of the island.

In most instances, these are not the islands discovered by the first white men who explored the Ohio. Nor are they those that will be known by the same names, thirty, forty, or fifty years hence. Their being gradually exchanged for others farther upward, produces an effect similar to what would be occasioned by the same islands moving against the stream, in their progress forcing the