They were often quite deep, and the water was so cold from the melting snows that we were nearly frozen each time we waded through them. We crossed several large flat basins of stones and gravel which appeared to have been lake-beds. In these basins we found deltas, formed by the stream dividing in various directions. We suffered tortures in crossing barefooted one cold stream after another.

The less soluble portions the waste brought in by streams and the waste of the shore form the muds and sands of continental deltas. All of these sea deposits consolidate and harden, and the coherent rocks of the land are thus reconstructed on the ocean floor. But the destination is not a final one.

If any one of the existing Swiss lakes were now lowered by deepening its outlet, or by raising the higher portion of it relatively to the lower, we should see similar deltas of comparatively modern date exposed to view, some of them with embedded trunks of pines of the same species drifted down during freshets.

The present rainfall would be wholly inadequate for agriculture, even if it were advantageously distributed over the lowlands, while in fact the greater portion is poured out on the heights in sudden and violent thundershowers called "cloud-bursts," the waters of which are fruitlessly swallowed up in sandy gulches and deltas a few minutes after their first boisterous appearance.

I observed in the Nepaul valleys what must be the case in every country in which the hills are composed of a soft material deltas formed by the soil which is washed down by the mountain torrents.

For ages, in spite of a gradual depression of the land and adjacent sea-bottom, the rivers continued to cover the sinking area with their deltas; until finally, the subsidence being in excess, the sea of the Middle Molasse gained upon the land, and marine beds were thrown down over the dense mass of fresh-water and brackish-water deposit, called the Lower Molasse, which had previously accumulated.

There are also several small parties of Wajiji, who have taken advantage of the fine lands in the deltas of the Kasokwe, Namusinga, and Luaba Rivers, the two first of which enter the Tanganika in this bay, near the head of which Nyabigma is situated.

The village to which we were going was on one of these deltas. Hardly had we set foot on shore than a violent earthquake almost threw us to the ground. The shock lasted for at least thirty seconds, then we heard a dull rumbling as of thunder, and saw how all along the coast immense masses of earth fell into the sea from the high cliffs, so that the water boiled and foamed wildly.

Formation of the delta of the Rhone The diluvial wash The alluvium spread over this The three stages the river pursues The zone of erosion The zone of compensation The zone of deposit River mouths Estuaries and deltas The formation of bars Of lagoons The lagoons of the Gulf of Lyons The ancient position of Arles between the river and the lagoons Neglect of the lagoons in the Middle Ages They become morasses Attempt at remedy Embankments and drains A mistake made The Camargue now a desert Les Saintes Maries No evidence to support the legend Based on a misapprehension.

The only thing that broke the sharply defined, clean upper surface of the triangular wing was a definite ridge that ran from the nose to the tail. In another second the three deltas made a slight left bank and shot by the B-25 at terrific speed. The colonels estimated that the speed was at least three times that of an F-86.