As the Red Cloud has been fully described in the volume entitled “Tom Swift and His Airship,” we will not go into details about it now. Sufficient to say that it was a combination of a biplane and dirigible balloon. It could be used either as one or the other, and the gas-bag feature was of value when the wind was too great to allow the use of the planes, or when the motive power, for some reason stopped. In that event the airship could remain suspended far above the clouds if necessary. There was provision for manufacturing the gas on board.
The Red Cloud was fitted up to accommodate about ten persons, though it was seldom that this number was carried. Two persons could successfully operate the machinery. There were sleeping berths, and in the main cabin a sitting-room, a dining-room, and a kitchen. There was also the motor compartment, and a steering tower, from which the engines could be controlled.
It was in this craft that the seekers after the diamond makers proposed undertaking the trip. Mr. Damon came on from his home in Waterfield about two days before the date set to leave, and Mr. Jenks, had, three days before this, taken up his abode at the Swift home. Mr. Parker, as has been stated, was already there, and he had put in his time making a number of scientific observations, though he had made no more predictions.
Nothing more had been seen of the mysterious man who had warned Tom, and the young inventor and Mr. Jenks began to hope that they had thrown their enemies off the track.
“Though I don't imagine they'll give up altogether,” said Mr. Jenks. “They're too desperate for that. We'll have trouble with them yet.”
“Well, it can't be helped,” decided Tom. “We'll try and be ready for it, when it comes,” and then, dismissing the matter from his mind, he busied himself about the airship.
The food and supplies had all been put aboard, and they expected to start the next morning. In order to make sure that any stones which they might succeed in getting from the diamond makers were real gems, a set of testing apparatus was taken along. Mr. Parker had had some experience in this line, and, in spite of the fact that he might make direful predictions, Tom was rather glad, after all, that the scientist was going to accompany them.
“But what is worrying me,” said Mr. Damon, “is what we are going to do after we get to Phantom Mountain. What are your plans, Mr. Jenks? Will you go in, and demand your share of the diamond-making business?”
“I have a right to it, as I invested a large sum in it, and I am entitled to more than a half-share. But, of course, I can't say what I'll do until I get there. We may have to act very secretly.”
“I'm inclined to think we will,” said Tom. “My plan would be to gain access to the cave, if possible, and watch them at work. We might be able to discover the secret of making diamonds, and, after all, that's what you want, isn't it, Mr. Jenks?”