When I looked again, the busy handling-machine had already put
together several of the pieces of apparatus it had taken out of the
cylinder into a shape having an unmistakable likeness to its own; and
down on the left a busy little digging mechanism had come into view,
emitting jets of green vapour and working its way round the pit,
excavating and embanking in a methodical and discriminating manner.
This it was which had caused the regular beating noise, and the
rhythmic shocks that had kept our ruinous refuge quivering.  It piped
and whistled as it worked.  So far as I could see, the thing was
without a directing Martian at all.