"One good thing, there wasn't any sort of a breeze. If it had been blowing fairly hard, the balloon would be twenty miles away by now, even if afloat."
"That's a fact Bluff; and as there wasn't an air current of more than a few miles an hour, one thing seems positive."
"What's that, Frank?" demanded Jerry.
"The balloon must have dropped into the water. If it was still in the air it could be seen through these powerful glasses miles away."
The others recognized the truth of his words.
"You seem to be heading straight out. Have you any reason for such a thing?" asked Bluff, seeking information.
"I have. Before we started I carefully noted my bearings. I also made sure that what little air was stirring came direct from the land, which, in this case, was almost due east. You can easily see from that which way the balloon must have drifted up to the minute it dragged in the water."
"Frank, what you say is sound, practical good sense. We must come on some sign in a short time, if we keep straight on and the conditions remain the same. I'm only afraid we may be too late," remarked Jerry sadly.
No one else spoke for several minutes as the motor-boat sped merrily along on her mission of mercy. It was a time of great strain. They hoped for the best, and yet were conscious of a terrible fear lest the professor and his assistant might have gone down long ere this.
"The breeze is freshening," remarked Bluff presently.