"Don't be alarmed," said Mr. Henderson. "It's all right, Washington. The table moves by some hidden mechanism, which doubtless was set in motion by the Martian who were just here, or the mere sitting down to our places may have started it."

They all got up to make an examination, and the table center at once ceased revolving, proving that some, connection existed between it and the chairs. But they could not discover the machinery. There was a small metal box underneath the table, but that was all.

"That must contain some of that marvelous red substance which gives light, heat and power," declared Mr. Roumann. "I must certainly get a supply of it. In fact, that is what I came to Mars for. That is the object of my trip, and if we can get a sufficient quantity of it, our fortunes are made."

"Is it so valuable?" asked Mark.

"It is the most valuable treasure in the universe," replied the German. "Long ago I suspected some such thing must exist on Mars, or else how, receiving only half the light and heat from the sun that we receive, can the inhabitants exist? And that they do live, and live well, we have seen. It must be due to the red substance, and if we could only get some back to earth it would be worth millions. Think of simply putting a bit of it in a stove and having heat, or hanging up some in a room and getting light from it. But, more than this, think of having it move machinery, I would not be surprised but what I could transform it into energy that would operate the motors of the Annihilator."

"But wouldn't you need a new supply every once in a while?" asked Jack.

"I think not. I believe it is like radium, and will last forever. In fact, you notice that the metal boxes it is contained in, except the ones in the boats, are securely sealed. If they had to be putting in a fresh supply every so often, they would make the boxes so they would open more easily. We must get some of that treasure."

"But how?" inquired Mr. Henderson.

"I don't know, but I will find out a way. When we have been here a few weeks we will be better acquainted with the Martians and their language, and can make a search."

"Well, if you folks is done talkin' about treasure, I'm goin' to eat," observed old Andy. "I'm hungry!"