It is, however, not narrow, and the descent is very small.

The depression in the surface of the desert, through which the water flows, is from five to ten miles wide, and, though it is nearly two thousand miles from the rainy district across the desert to the sea, the country for the whole distance is almost level.

There is only sufficient descent, especially for the last thousand miles, to determine a very gentle current to the northward in the waters of the stream.
Under these circumstances, the immense quantity of water which falls in the rainy district in these inundating tropical showers, expands over the whole valley, and forms for a time an immense lake, extending in length across the whole breadth of the desert.

This lake is, of course, from five to ten miles wide, and a thousand miles long.

The water in it is shallow and turbid, and it has a gentle current toward the north.