The method by which the balsas are directed in their course is extremely ingenious, and is that to which I should wish to call the attention of sailors, not merely as a matter of curiosity, but from its practical utility in seamanship.  No officer can tell how soon he may be called upon to place his crew on a raft, should his ship be wrecked; and yet, unless he has been previously made aware of some method of steering it, no purpose may be answered but that of protracting the misery of the people under his charge.  Nothing can be more simple, or more easy of application, than the South American contrivance.  Near both ends of the centre spar there is cut a perpendicular slit, about a couple of inches wide by one or two feet in length.  Into each of these holes a broad plank, called guaras by the natives, is inserted in such a way that it may be thrust down to the depth of ten or twelve feet, or it may be drawn up entirely.  The slits are so cut, that, when the raft is in motion, the edges of these planks shall meet the water.  It is clear, that if both the guaras be thrust quite down, and held fast in a perpendicular direction, they will offer a broad surface towards the side, and thus, by acting like the leeboards of a river-barge, or the keel of a ship, prevent the balsa from drifting sidewise or dead to leeward.  But while these guaras serve the purpose of a keel, they also perform the important duty of a rudder, the rationale of which every sailor will understand, upon considering the effect which must follow upon pulling either up the guara in the bow or that in the stern.  Suppose, when the wind is on the beam, the foremost one drawn up; that end of the raft will instantly have a tendency to drift to leeward, from the absence of the lateral support it previously received from its guara or keel at the bow; or, in sea language, the balsa will immediately “fall off,” and in time she will come right before the wind.  On the other hand, if the foremost guara be kept down while the sternmost one is drawn up, the balsa’s head, or bow, will gradually come up towards the wind, in consequence of that end retaining its hold of the water by reason of its guara, while the stern end, being relieved from its lateral support, drifts to leeward.  Thus, by judiciously raising or lowering one or both the guaras, the raft may not only be steered with the greatest nicety, but may be tacked or wore, or otherwise directed, with precision.

I never shall forget the sensation produced in a ship I commanded one evening on the coast of Peru, as we steered towards the roadstead of Payta.  An immense balsa was dashing out before the land-wind, and sending a snowy wreath of foam before her like that which curls up before the bow of a frigate in chase.  As long as she was kept before the wind, we could understand this in some degree; but when she hauled up in order to round the point, and having made a stretch along-shore, proceeded to tack, we could scarcely believe our eyes.  Had the celebrated Flying Dutchman sailed past us, our wonder could hardly have been more excited.