“How long a trip do you expect to make?” asked the professor, while his eyes roved about in search of any possible stray insect worth catching.

“Well, I hope to be up in the air at least two nights,” said Mr. Glassford. “Of course, one can never tell exactly what is going to happen. You know there are two prizes of twenty-five hundred dollars each. One will be given the owners of the motor ship which remains up the greatest number of hours, and the other to the machine which travels the longest distance.”

“Then there is a possibility of us getting both prizes, is there not?”

“A possibility, yes, but no probability, though I hope we will get one prize.”

To be sure that nothing was lacking to make the trip a success, Mr. Glassford, aided by the boys, went over every inch of the motor ship, and tested the motor. It seemed to work well.

An extra supply of gasolene and water had been put on board, together with plentiful stores and supplies, the recording and measuring instruments, and everything that ingenuity or science could suggest to make the trip a success.

There were five other motor ships entered in the race. They were all forms of the dirigible balloon, of various shapes and sizes, but none had the aeroplane arrangement that the Comet possessed. Three of the airships were larger than the craft of the motor boys, and the remaining two were somewhat smaller. All were powerful machines, and in tests all had shown that they could go up to a great height and move with considerable speed in the air. Owing to Hoswell’s action, the Comet had been tried only once at Park Haven, and aside from her owners, few felt that she would make much of a showing. The “favorite,” if one may use such a term, was a large red balloon, and when Mr. Glassford saw it coming from the big tent, not far from where the Comet was sheltered, he shook his head rather dubiously.

“That’s a fine machine,” he said. “Her propellers look to be more powerful than ours, but I think we can do better if it comes on to blow, which it is very likely to do.”

“Oh, we’ll win,” said Bob confidently.

Word was given for all six of the big balloons, that were to take part in the race which was to formally open the carnival, to prepare to start. Some had already left the sheltering sheds or tents, and now the Comet’s nose was poked out.