"My! but that was a narrow escape!" exclaimed Nan, as she skated slowly
about. "My heart is beating fast yet."

"So's mine," added Flossie. "Did he do it on purpose?"

"No, indeed!" exclaimed Bert. "I guess Mr. Watson wouldn't do a thing like
_that!_ He was looking after the ropes of the sail, or doing something to
the steering rudder, and that's why he didn't see you and Freddie."

"What makes an ice-boat go?" asked Freddie.

"The wind blows it, just as the wind blows a sailboat," explained Bert,
looking down the lake after the ice-boat.

"But it hasn't any cabin to it like a real boat," went on Freddie. "And it
doesn't go in the water. Where do the people sit?"

"An ice-boat is like this," said Bert, and with the sharp heel end of his
skate he drew a picture on the ice. "You take two long pieces of wood, and
fasten them together like a cross--almost the same as when you start to
make a kite," he went on. "On each end of the short cross there are double
runners, like skates, only bigger. And at the end of the long stick, at
the back, is another runner, and this moves, and has a handle to it like
the rudder on a boat. They steer the ice-boat with this handle.

"And where the two big sticks cross they put up the tall mast and make the
sail fast to that. Then when the wind blows it sends the ice-boat over the
ice as fast as anything."