The well itself was sufficiently remarkable. Our work took us some twelve
feet from the surface, and in the well we had nearly five feet of water
and the probability of a deal more, as we had not reached "bottom." The
question that presented itself to my mind was whether the natives had
sunk the well on a likely looking spot and been fortunate in finding a
supply, or whether, from tradition, they knew that this well, possibly
only a rock-hole covered by surface soil, existed. The depression in
which the well is situated must after rain receive the drainage, not only
from the channel we followed, but from the stony rise to the north of it.
After a heavy storm--and from the way in which this creek has been torn
through the sand, scouring a channel down to bedrock, it is clear that
occasionally violent storms visit this region--a large volume of water
would collect in this depression. Some of it would be sucked up by the
trees and shrubs, some would evaporate, but the greater part would soak
into the ground where, so long as the bed-rock (which in this particular
case is a hard sandstone and iron conglomerate) is impervious, it would
remain. I should think it likely, therefore, that on this and similar
flats, not far from hills or tablelands, water by sinking could be
obtained at no great depth. A good guide to this well is a bare patch of
rock on Mount Colin, which bears 138 degrees three miles distant.

This hill is visible from ten miles due North of the well, from which
point it shows up prominently. Continuing a northerly march from that
point we found that the gravel and stones for the next few miles became
much rougher, and made walking tiring work. Occasionally mulga thickets
free from stones had to be passed through; in these there often occurred
very shallow depressions overgrown with grass and floored with clay. From
the floors rose high, pinnacled ant-heaps, built by the white ant; these
hills, grouped into little colonies, sometimes attained a height of
eleven feet, and had in the distance a weird appearance, reminding me in