"Perhaps I had better explain from the beginning," interrupted Mr. Henderson.
"Maybe it will be better," assented the other.
"Boys, be seated," spoke their guardian, and Jack and Mark took chairs. "Mr. Santell Roumann is an inventor, like myself," went on Mr. Henderson. "I have known him for several years, but I had not seen him in a long time, until he called on me the other day with his strange proposition. We used to attend the same college, but since his graduation he has been experimenting in Germany."
"Where I discovered the secret of the wonderful power that will take us to Mars," added Mr. Roumann.
"That is one point on which we differ," continued Mr. Henderson. "Mr. Roumann believes we can get to the red planet, which, as he correctly says, is nearer to us now than it will be again in many years. I do not see how we can get there through the intervening space."
"And I will prove to you that we can," insisted the other. "The power which I shall use is strongest known. But it depends on you and your young assistants."
"On us?" asked Jack.
"Yes," replied Mr. Santell Roumann. "If you and Professor Henderson can build the proper projectile, we shall go."
"A projectile!" exclaimed Jack.
"A projectile," said Mr. Roumann again. "I have studied it all out, and I think the projectile, shaped somewhat like a great shell, such as they use in warfare, or, more properly speaking, built like a cigar or a torpedo, is the only feasible means of reaching Mars. We shall go in a projectile, two hundred feet long, and ten feet in diameter at the largest point. That will offer the least resistance to the atmosphere of the earth, though when we get within the atmosphere of Mars, and are subjected to its attraction of gravitation, we shall meet with even less resistance."