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.