atmosphere, Mr. Damon. Tom and I are getting to be old hands at it.
But, if you think you can stand it, I'll go up about a thousand feet
higher."

"Make it two thousand, while you're at it," proposed the odd
character. "Might as well take a long fall as a short one."

Accordingly, the elevation rudder was used to send the Red Cloud to a
greater height while she was still skimming along like some great
bird. Of course the desired elevation could have been obtained by
forcing more gas from the machine into the big, red container
overhead, but it was decided to be as sparing of this vapor as
possible, since the voyagers did not want to descend to get more
material, in case they used up what they had. It was just as easy to
rise by properly working the rudders, when the ship was in motion, and
that was the method now employed.

With the great propellers, fore and aft, making about a thousand
revolutions a minute the craft slanted up toward the sky.

The ship was not being run at top speed as Mr. Sharp did not care to
force it, and there was no need for haste. Long distance, rather than
high speed was being aimed at on this first important flight.

Tom was at the steering wheel, and, with his I hand on the lever
controlling the elevation rudder, kept watch of the face of Mr. Damon,
occasionally noting what height the hand on the gauge registered. He
fancied he saw the cheeks of his friend growing pale, and, when a
height of thirty-five hundred feet was indicated, with a yank the
young inventor put the airship on a level keel.