"Look ahead of us!" said Joe. "There isn't room even for a path. A board walk has been fastened with iron rods to the wall. It hangs right over the rushing water. What if it should break while we are on it! I am not sure that I want to go any farther."
"Come, now, don't be a coward, Joe," said his father. "The Swiss government builds these paths, and they are built strong. We are safe."
So on they tramped through the great crack in the mountain. In some places the path hung high over the swift waters. In other places it was tunneled through the dark rocks. But always it followed the deep, narrow crack, with the noisy river at its bottom and a bit of blue sky far, far above.
For nearly a mile the boys followed this path. In many places the river was so noisy they had to shout to make each other hear. But at last they came out on the other side of the mountain.
They had not climbed the mountain, and they had not gone around it. They had gone through it. And more wonderful still, the great river Aar has been carrying its waters through the mountain for ages and ages.
Close beside the river, at the end of the path, was a tiny shop kept by a little old woman and her granddaughter.
The little girl served the boys to raspberry lemonade, and she sold them picture post cards showing the strange path over which they had just come.
Then back they went into the mountain crack—over the footpath hanging high above the rushing water, and through the small, dark tunnels, until once more they were in the lovely green valley of Meiringen.