"There may have been," Bertie said. "I was hanging so close to the wall that there may very well have been one without my being able to see it. But it looks pitch-dark in there. If there were much of an opening we ought to see the light, for, as we agreed, it can't be more than a hundred feet long."

"That is the first place we will investigate, Bertie. The question of how we are to get into the house wants some thinking over. That lowest window is a good twenty-five feet above the ground."

"Of course if we had a grapnel we could fasten it to the end of a rope and chuck it in."

"We shall have to make something of that sort. If the window had been on the other side instead of this it would have been easy enough, because I could have lowered you and slipped down the rope afterwards, but that arch sticking out so far on this side makes it impossible. All that we can do now is, as far as I can see, to lower ourselves down on to the top of that wall in the ravine, then go and examine the tunnel. We have got plenty of rope to lower ourselves from here on to the wall."