course for the lake, but wound now to the right and again to the
left, according to the solidity of the ground. In addition to these
sinuosities there were several pockets or alcoves along the tunnel,
as if the stream had here found passage for a short way, and was then
obliged to recede. The walls were oozy, and little rivulets trickled
through, and went rippling over the floor of the passage.

'A short distance from the dwelling,' Nancy explained, 'a dam has
been put before this stream, and it runs through a channel which they
cut for it into Silent Lake.'

The two explorers now reached a point well lighted, and turning up
his eyes Roland observed a number of holes in the roofing.

'Ah; this is a treacherous spot,'

'Yes; and from here nearly to the end of the passage the roof is
much like that. It was all along here that the men who came into the
bush fell through; and as they fell the old woman, Poll, and The
Lifter despatched them with clubs. Did you never wonder why we are
risky enough to light fires by night and assemble by day on the open
ground?'

'I have thought that the risk was great, indeed; but I had no way of
accounting for it.'

'Well, it is impossible for anybody to approach without having to
cross this tunnel at its dangerous part. Why, the very day before you
came amongst us, some young man, after woodcock in the swamp, strayed
down this way, saw water glimmering beyond him and walked towards it.