ne 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.

It will generally be found well worth an officer's attention to remark
in what ma