The steam yacht was moving slowly and those in the two rowboats were making every effort to catch up to her. Then the black smoke began to pour from the funnel of the Josephine.
"The other vessel is getting up steam," said Mr. Rover. "She may catch the Rainbow even if those in the rowboats do not."
Closer and closer to the steam yacht drew the two rowboats, until it looked as if the Rainbow would surely be boarded by the enemy. Then of a sudden there came a cloud of smoke from the deck of the steam yacht, followed by a stream of sparks which went whizzing just over the rowboats. Then followed more sparks, and balls of fire, red, white and blue.
"What in the world are they doing?" murmured Captain Barforth.
"They are shooting off something, but it is not a gun or a cannon," answered Mr. Rover.
"Hurrah! I know what it is!" cried Tom "Good for Fred and Hans! Those are my fireworks—those I had left from the Fourth of July celebration. They are giving them a dose of rockets and Roman candles!"
This news was true, and as the rockets and Roman candles hit the rowboats and the occupants the latter stopped rowing and then began to back water in confusion. Soon the rowboats turned back and hastened to the side of the Josephine.
"That's what I call repelling boarders!" said Captain Barforth, grimly. "I only hope the fireworks hold out."
"It is now to be a race between the Rainbow and that other craft," observed Mr. Rover, and he was right. Inside of fifteen minutes both vessels were headed out to sea, and running at about the same rate of speed. Soon the haze over the water hid both craft from view.
"Well, one thing is certain," said Mr. Rover. "Our friends are alive to their danger and are going to do their best to get away from the enemy."