All three said they did.

“Then I’ll divide our forces,” went on the captain and owner of the Monarch.  “I will be in general charge of the ship, just as if I was a commander of an ocean steamer.  I expect to be obeyed in every particular.  Washington will be the engineer, with the two boys to help him.  Tom Smith and Bill Jones will be in charge of the kitchen, and I will show them how to prepare the condensed foods.  Andy Sudds will be a sort of look-out and the hunter of the expedition.  I will steer the ship and keep watch of the different instruments.

“In order that you may know a little bit about the Monarch I will tell you how she is run.  In the first place, she is lifted above the earth by the power of a very strong gas I discovered.  It is much lighter than hydrogen, or the gas ordinary airships are filled with, and has a greater lifting power than the hot air used in the old balloons.

“By putting more gas into the silk bag above us I can rise higher.  The less gas I use the lower we go.  The gas is let into or out of the bag by means of valves which are operated from the engine room or the steering tower.  The forward motion of the ship is brought about by means of the propeller at the stern.  This propeller works by electricity.  The electricity comes from storage batteries which are kept charged from the dynamo run by one of the gasolene engines.  I also have an electric motor that is run by either a gasolene engine or the storage battery.  If one breaks down I can use the other.  The motor alone will run the propeller if the storage batteries fail, and I have to run the electric machine directly from the gasolene engine.

“That apparatus there,” and he pointed to a complicated machine, “is where the lifting gas is generated.  A gasolene engine runs it.  Those tubes carry the gas from the machine to the bag above.”

Then the professor pointed out the levers that started and stopped The Monarch, those that sent it higher into the air or toward the earth, the wheel for steering, and told the boys and men how to read the instrument that gave the heights, the force of the wind, the temperature, and much other information.  He showed them how the entire control of the ship could be accomplished from the conning or steering tower by the turning of one wheel or another.

“Rattlesnakes an’ mud turtles, but she sure is a bang-up affair,” observed Andy Sudds.  “But about that gun—­”

“That’s so.  I promised you a gun in exchange for the one you lost,” said Mr. Henderson.  “Wait a moment.”

He was gone a little while.  Presently he returned with a fine rifle, at the sight of which the old hunter’s eyes sparkled.

“That’s a beauty!” he exclaimed.  “It beats mine.”

“It is a magazine gun,” explained the professor.  “It fires sixteen shots with one loading,” he explained.

“And I can kill sixteen white bears, sixteen seals or sixteen whales!” exclaimed Andy with delight.  “Well, I certainly am glad I come along, Professor.”