called it Etherium, for the reason that I expect it to carry us
through the ether, or space that exists outside of the atmosphere
of this earth and that of Mars.

"Now, professor, do you think you and your assistants can build a
proper projectile?"

"We built an airship that went to the North Pole, we constructed
a submarine that took us to the South Pole, and we had the Flying
Mermaid, in which we went to the center of the earth," said Mr.
Henderson. "I think we can build you the torpedo-shaped
projectile. But what will make it move through thirty-five
millions of miles of space?"

"I will!" exclaimed the other. "I and my wonderful, secret
power--Etherium! If you will build the projectile I will do the
rest. I will give you the plans for the machinery at once, and
you can begin as soon as you are ready. You have a large
workshop here, I understand."

"Yes, we have all the means at our command," admitted Mr.
Henderson.

"But it must be built in secret," stipulated Mr. Roumann. "No
one must know about it until we are ready to leave. Several
unscrupulous men have tried to steal my secret."

"We can construct the projectile and machinery so that no one but
ourselves, and one or two trusty mechanics, will ever know about
it," promised Mr. Henderson.