, saying that this was the place
to camp, and the Black Tanks were on the southern side of the spur,
three miles distant.

In a few minutes, with the horses and mules divested of saddles,
bridles, and harnesses, leaving two men behind to guard the property
and collect fuel for a fire, we were on the way to water.

Hurrying along, we saw before us a long, irregular range, apparently
three thousand feet in height, which had been cleft from summit to
base as if by a wedge. In this rent we found water--water deposited in
a natural reservoir by the periodical rainfalls in millions of
gallons, a reservoir never known to be dry.

Climbing over the dike which enclosed the main deposit, we descended
to the cistern, filled our cups, and swallowed the contents without
taking a breath. When we dipped up a second, Tom Clary looked into the
depths of his cup with knitted brows.

"Whist, now, sergeant laddies!" he exclaimed. "Look into the wather!
It's aloive with wigglers of ivery variety. They're 's plinty as pays
in a soup."

"Ugh! And we are full of them, too, Tom," said Henry, looking into his
cup with narrow-eyed anxiety.

Pausing in the act of taking a second drink, I looked into my cup, and
saw that it contained myriads of animalcula and larvae, which zigzagged
from side to side in the liveliest manner.

"Will they hurt us, Tom?" questioned Henry.

"I rickon they've got the worst of it, sergeant laddie; but I think
I'd fale a bit aisier if I was blindfolded or takin' a drink in the
dark. I prefer me liquid refrishment with a little less mate, not to
minshin its bein' less frisky."

We had come to the Cisternas Negras with towels, intending to wash off
the dust of travel. We now used one of them to strain the water, and
were astonished to see that each gallon left behind it a plump
spoonful of animalcula. The water was sweet, but, after discovering
the abundant life in it, we deferred drinking more of it until it had
been boiled.

As we pursued the narrow path to camp in single file, we noticed Vic a
considerable distance to the right, scouting and nosing about in an
earnest manner. Evidently she thought she had made an important
discovery, for she several times paused and looked in our direction
and barked. But we were too hungry to investigate, and soon she
disappeared from our view.

When we reached the ambulance the boys put a few cakes of hard bread
in their pockets, and, taking their shot-guns, went out to