"All right, let's try it," answered Dave and Roger, and the three set to work to make a round, hard ball. They rolled it around the top of the hill until it was all of three feet in diameter and then pushed it to the edge.
"Now then, send her down! " cried Phil, and the three boys gave a push that took the big snowball over the edge of the hill. Slowly at first and then faster and faster, it rolled down the hill, increasing in size as it progressed.
"It's getting there! " sang out Roger. "See how it is shooting along!"
"Look!" yelled Dave, pointing up the river. "An ice-boat is coming!"
All looked and saw that he was right. It was a craft from the Rockville academy, and it was headed straight for the spot where the big snowball was about to cross.
"If the snowball hits them, there will be a smash-up!" cried Roger.
"And that is just what is going to happen, I fear," answered Dave.