The two boys were delighted to have a chance in the engine room.  Under Washington’s direction, the colored man showing quite a knowledge of the apparatus, they oiled the various bearings until everything was running smoothly.

Until now they had no time to realize what an experience they were going through.  Things had happened so quickly that it was hard to realize they were sailing through the air in a wonderful ship, probably the most successful navigator of the upper regions ever invented.

It was not until Jack looked over the edge of the airship from the engine room window that he felt what a trip up among the clouds meant.  Below the earth was spread out like a good-sized map, with little threads of silver for rivers, patches of green for big fields, and narrow gray ribbons where there were roads.

“It’s wonderful!” he cried to Mark.

“And to think we were chased out of town yesterday by a constable,” spoke his companion.  “This is a great change.  I’d like to see him catch us now.”

“Dis prolonguated elevation into de airy space ob de zeneth am extremely discommodatiousness to a pusson what ain’t used to it,” remarked Washington with a broad grin as he oiled a whirring motor.

“Yes—­er—­I guess it is,” admitted Mark.

“Are your teeth all fast after that effort?” asked Jack with a laugh.

“Neber yo’ mind my teeth,” said Washington.  “Golly!  What’s de matter now?”

The Monarch was darting from side to side like a kite that has lost its tail in a high wind.

“It’s only the professor trying the steering apparatus,” said Jack, looking forward toward the conning tower.  This proved to be true, for, in a moment, the airship resumed a straight path, and the professor, coming back to the engine room, cried: 

“She answers her helm perfectly.  It certainly is a success in every way!  But now, since the machinery is working well, and I have the Monarch headed due north, in which direction she will sail alone for a while, I want you boys to come into the dining room, while we talk over matters with our unexpected visitors.  We must lay plans and divide up the work of running the ship.”

Jack and Mark went with the old man into the middle room of the craft.  There they found the old hunter and the two farm hands.  None of the three had quite gotten over his fright at being suddenly carried off through the air.

“Everything has turned out for the best,” the inventor began.  “I feared my forced start would spoil my plans, but you see I got a crew almost at the last moment.  Now we will—­”

He was interrupted by a sudden cry from the engine room.

“Help!  Help!” rang out the voice of the colored man.  “Hurry up an’ help, Perfessor.  I’m caught in some cantankerous conglomeration an’ I’m bein’ killed!  Help!  Help!”

Followed by the boys and the three men the old inventor hastened aft, alarm showing on his face.