y, and some of them
were evidently about to pass right overhead.

"They'll come over the wagons," said Du Plessis; "they're off for that
big salt pan we passed yesterday morning."

I dived into my wagon, and took down my rifle. An idea had struck me.
I pushed a cartridge into the breech, and, as the great birds passed
slowly a hundred yards overhead, took aim at one and fired. The target
was a big and an easy one: the stricken bird toppled downwards, turning
over and over in its fall, and presently hit the earth with a tremendous
thud. One of the boys ran and brought it to me. I opened its bill.
The pouch contained seven fresh fish--six smallish and carp-like,
well-known to the Boers as _karpers_, the seventh a "yellow fish," a
barbel-like fish of a pound and a half.

"Here, Koenraad," I said to my companion, "is proof positive that your
mysterious vlei lies in the mountain and holds water. These fish are
fresh--they were caught early this morning; and the birds are away to
the salt pan for the day to eat and digest them."

We finished breakfast hastily, and sallied forth on our search. First,
we followed the tiny stream near which we were camped. This led us to
the westerly side of the mountain, and manifestly took its rise in some
marshy ground immediately beneath the rock walls. A careful examination
convinced me that the marsh itself owed its origin to some subterraneous
escape--very probably from the vlei itself--from within the mountains.
But there was no hope of ingress in that direction. Pursuing our
investigations, we rode carefully round the whole western and southern
face of the mountain-wall, scanning closely every yard of its surface.
This mountain-wall ran in a great semicircle; its dark-red, rampart-like
cliffs were sheer, and wonderfully free from projections and
undergrowth. We spent the whole day searching for any trace of path or
ingress, and retired to our wagons for the evening completely
discomfited. There was not foothold for the hardiest cliff climber that
ever risked his life in search of wildfowl eggs.

Next morning, we followed this cliff face along the southerly aspect.
Here, after a little way, it was met by another mass of mountains, into
which it ran, terminating in a chimney-like _cul-de-sac_ at the end of a
short narrow gorge. Here, too, apparently, there was no possible
approach upward or inward.

"It was here," said Du Plessis, "that the spoor of my cousin was last
s