“ Giv akt! ”

“Attention!” repeated my uncle.

In half an hour we were standing upon the surface of a rock jammed in across the chimney from one side to the other.

Hans pulled the rope by one of its ends, the other rose in the air; after passing the higher rock it came down again, bringing with it a rather dangerous shower of bits of stone and lava.

Leaning over the edge of our narrow standing ground, I observed that the bottom of the hole was still invisible.

The same manoeuvre was repeated with the cord, and half an hour after we had descended another two hundred feet.