At the end of five or six days we had got through the face of the rock, and we found the stone soft. In a day or two more we came to what was but hard clay, which gave way at a slight blow from the axe.
"We need not fear now," said I, "for we shall soon have a hole as large as we want."
With the earth we took out we made a ridge in front of the cliff. The boys now got on so well, and dug so much out, that I had hard work to throw up the earth on the bank.
One day, as Jack stuck his pick in at the back of the cave, which was now more than eight feet from the front, a great mass of the rock fell in, and he cried out, "Look here! I have got through."
"Through what?" said I. "Not through your hand, I hope."
"No, no, but through the rock."
At this, Fritz set up a loud laugh.
"Why not say through the world at once, and push your crow bar in till you reach EU-ROPE, which, Ernest says, lies in a straight line from our feet. I should like to have a peep down, such a hole, for I might thus get a sight of our dear Swiss home."
Fritz and I went up to the wall and found that Jack was right, for he had come to a clear space. His first thought was to jump in; but as I knew that there might be foul air in the cave, I would not let him risk his life.
The boys then set fire to some dry grass, and thrust it in the hole, but it went out at once, which was a sure sign that the air was not fit to breathe.