From Corrientes to La Paz the river flows from north to south at the feet of the Corrientes cliffs. These line the main stream between Corrientes and Empedrado, and for thirty-five miles south of Bellavista. In the latitude of Riachucho, especially about Bellavista, the cliffs form a series of creeks and capes, in which the west winds create a heavy sea that was dreaded by ships of light draught coming down the river. North of Bellavista, and for more than a hundred miles south of Goya, the main stream is separated from the cliff by a series of alluvial islands; behind these are lateral arms (_riachos_) into which pour the rivers of Corrientes. These arms were much used by the early navigators. Between Esquina and La Paz the main bed, which is not in touch with the land on either of its banks, flows in a meandering path for some seven miles, the scale of the bends being double that of the meandering of the Paraguay north of the confluence. The islands are very small, and are strung in a rosary at the top of each bend. The depth is sixty feet at the top of the bend. The shallows are in a line with the islands at the point where the current runs evenly again before the next curve. The depth here is seven, and sometimes even five feet.[126] These shallows change their places quickly, and it is not always the same bad spot that determines the maximum draught for ships that are to be used in this section. This migration of the shallows is very different from the permanence of the rocky bottom of the stretch between Corrientes and Posadas. [126] In point of fact, the ridge is lower at the time of low water, when the current is concentrated in the main channel, so that one always finds one or two feet greater depth there at low water than soundings taken at high water would lead one to expect. From La Paz to Parana the main course is outlined by the Entre Rios cliffs. There is no further meandering. The cliffs of hard rock offer far more resistance than the soft alluvia over which the river wanders freely. The permanence of the bed in front of the cliffs leads to a depth of as much as eighty feet. Only here and there a fringe of alluvial stuff separates the channel for a time from the cliff. These curves seem, as a rule, to coincide with the confluence of rivers, which bring a heavy load of clay from the tableland; as, does, for instance, the San Feliciano, north of Hernandarias. They are marked by shallows, in strong contrast to the great depths of the straight sections. The San Feliciano _paso_, which is twelve feet broad to-day, was only six feet broad in 1908. It appeared on Sullivan's map in 1847.[127] [127] A little above its actual position.