m side to side, was under my observation--so completely,
that I could distinguish the smallest object that might have appeared
upon its surface. Not even the tiniest waif could have escaped me--much
less a canoe freighted with human beings; and containing that fairer
form, that would be certain to secure the keenest and most eager glances
of my eye.

I congratulated myself on reaching this perch. I perceived that a
better post of observation could not have been chosen. It was complete
for the purpose; and, if I could only have felt sure that we had arrived
in time, all would have been satisfactory. Time alone would determine
the point; and, turning my eyes up stream, I entered upon my earnest
vigil.

CHAPTER THIRTY EIGHT.

THE WHITE FOG.

Vain vigil it proved. I shall not tire the reader with details.
Suffice it to say, that we kept watch till morning's dawn; and then,
profiting by the daylight, sought out a more convenient post of
observation, where we continued our surveillance--watching and sleeping
in turn. Throughout the following day, and into the second, was our
vigil extended: until no longer able to hope against hope, we agreed
finally to abandon it. But for one circumstance, we might have felt
surprise at the result. We were both convinced that we had reached the
river's mouth in good time: since, by our calculations, the canoe could
not possibly have "headed" us. But for the same circumstance, we might
have believed, that they had not yet come down the Obion; and perhaps
would have remained at our post a day longer.

The explanation is this: On the first night of our watch, a few hours
after having taken my station in the tree, a fog had suddenly arisen
upon the rivers, shrouding the channels of both. It was the _white
fog_--a well-known phenomenon of the Mississippi--that often extends its
dangerous drapery over the bosom of the "Father of Waters:" a thing of
dread, even to the skilled pilots who navigate this mighty stream. On
that particular night, the fog lay low upon the water: so that in my
position near the top of the tree I was entirely clear of its vapoury
disc; and could look down upon its soft filmy cumuli floating gently
over the surface--white and luminous under the silvery moonlight. The
moon was still shining brightly; and both sky and forest could be seen
as clearly as ever. The water-surface alone was hidden from my sight--
the very thing I was most anxious to observe.