“Good!  The very thing!” shouted Tom.

“Mr. Fenwick lives near there,” went on Mr. Damon, and Tom nodded comprehendingly.

They were now over North Philadelphia, and, in a few minutes more were above the Quaker City itself.  They were flying rather low, and as the people in the streets became aware of their presence there was intense excitement.  Tom steered for the big athletic field, and soon saw it in the distance.

With a suddenness that was startling the motor ceased its terrific racket.  The monoplane gave a sickening dip, and Tom had to adjust the wing tips and rudder quickly to prevent it slewing around at a dangerous angle.

“What’s the matter?” cried Mr. Damon, “Did you shut it off on purpose?”

“No!” shouted Tom, “Something’s gone wrong!”

“Gone wrong!  Bless my overshoes!  Is there any danger?”

“We’ll have to vol-plane to earth,” answered Tom, and there was a grim look on his face.  He had never executed this feat with a passenger aboard He was wondering how the butterfly would behave.  But he would know very soon, for already the tiny monoplane was shooting rapidly toward the big field, which was now swarming with a curious crowd.

CHAPTER VI

THE NEW AIRSHIP

For a brief instant after the stopping of the motor, and the consequent sudden dropping toward the earth of the monoplane, Tom glanced at Mr. Damon.  The latter’s face was rather pale, but he seemed calm and collected.  His lips moved slightly, and Tom, even in those tense moments, wondered if the odd gentleman was blessing anything in particular, or everything in general.

Tom threw up the tilting plane, to catch more air beneath it, and bring the butterfly in a more parallel position to the earth.  This, in a manner, checked the downward flight, and they glided along horizontally for a hundred feet or more.

“Is—­is there any great danger, Tom?” asked Mr. Damon.

“I think not,” answered the young inventor, confidently.  “I have done this same thing before, and from greater heights.  The only thing that bothers me is that there are several cross-currents of air up here, which make it difficult to manage the planes and wing tips.  But I think we’ll make a good landing.”

“Bless my overcoat!” exclaimed Mr. Damon “I certainly hope so.”

Conversation was more easily carried on now, as the motor was not spitting fire and throbbing like a battery of Gatling guns.  Tom thought perhaps it might start on the spark, as the propeller was slowly swinging from the force of air against it.  He tried, but there was no explosion.  He had scarcely hoped for it, as he realized that some part of the mechanism must have broken.

Down they glided, coming nearer and nearer to the earth.  The crowd in the big athletic field grew larger.  Shouts of wonder and fear could be heard, and people could be seen running excitedly about.  To Tom and Mr. Damon they looked like dolls.