"We are traveling that many miles a second," went on the scientist. "The atmospheric motor is not working as fast as I hoped it would, but we are going fast enough. When we start the Etherium machine we shall go much more speedily."
"And when will that be?" asked Mark.
"I can't tell exactly. It will not be until we have passed through the atmosphere of the earth, and there is no way of ascertaining in advance just how thick that stratum is."
"Then how will you know?" asked Jack.
"By means of my instruments. When the hand on this dial points to zero I will know that we are beyond the atmosphere, and that it is time to start the Etherium motor."
"How do you know in which direction to steer?" asked Mark. "Can you see anything out of that window?"
"Not a thing," replied the German. "Look for yourself."
Jack and Mark peered through the plate glass. All they could see was a sort of white, fleecy mass of clouds that surrounded the great projectile.
"It's just like when we were above the clouds in the Electric Monarch," said Jack.
"Exactly," agreed Mr. Henderson.