as any feller I ever see, und you nefer say nodding ondil it shlips oudt, like vat it toes now."

Motor Matt made no answer to this. Just then his attention was completely absorbed by the air-craft.

As near as he could judge, the cigar-shaped gas-bag was more than a hundred feet long. Beneath the bag was suspended a light framework. Midway of the framework was an open space, containing a chair in which sat the man who was handling the motor. Out behind the driver the framework tapered to a point, and at the end of this rearmost point was the whirling propeller. The glittering blades caught the sun in a continuous sparkling reflection, which made the air-ship appear to be trailed by a glow of fire.

Forward of the cockpit, or open space, was the motor. A rail ran around the cockpit.

There were two men in the car—the one in the driver's seat and another in front of him, leaning over the rail. This second man seemed to be looking at the two boys, and to be waving his hand and giving directions to the driver.

Along the side of the gas-bag Matt was able to read the name "Hawk," printed in large letters.

The Hawk was about a hundred feet above the surface of the earth. A long rope depended from the car, and twenty or thirty feet of it dragged along the ground as the car moved.

"Vat's der rope for, Matt?" inquired Carl.

"If that was an ordinary balloon," replied Matt, "we'd call the rope a guide-rope. Usually the guide-rope helps to save gas and ballast. When you want a balloon to go up, you know, you throw out sand; when you want it to come down, you let out gas. That trailing rope acts as ballast. When the gas expands, and the ship wants to rise, part of the rope that trails is lifted from the ground and throws more weight on the car; and when the gas contracts, and the car shows a tendency to descend, more of the rope falls on the ground and takes just that much weight off the car."

"Dot's as clear as mud!"

"I can't understand why they've got a drag on the air-ship," muttered Matt. "I supposed the propeller and the steering-blades were enough to send such a craft wherever it was wanted to go."

As the Hawk came nearer, Matt's trained eyes and ears convinced him that the driver of the air-ship was a poor motorist. Evidently he did not understand the engine he was handling. The air-ship zigzagged erratically on its course, and the long bag ducked upward and downward in a most hair-raising manner. On top of that, Matt could hear one of the cylinders misfiring.

The Hawk's drag-rope was trailing along the roadway. First it was on one side of the road, and then on the other, following the irregular swaying and plunging of the car.

"Come on, Carl!" called Matt, turning and running for the automobile. "If that rope strikes our car it may damage it. We've got to fend it off."

"Dose air-ship fellers vas mighdy careless!" answered Carl, hurrying after his chum. "Dot rope mighdt knock town fences, und preak vinders, und do plendy more tamages."

"There isn't power enough at the other end of it to do much damage," Matt answered, posting himself at the rear of the automobile and watching the advancing rope with sharp eyes.

By that time the Hawk was almost over the boys' heads. The rope, of course, was dragging far out behind, and the trailing part of it bid fair to pass the car well on the right.

"Hello, there!" shouted the man at the rail of the Hawk, leaning far over and making a trumpet out of his hands.

He seemed to be excited, for some cause or other.

"Hello yourseluf, vonce!" called back the Dutch boy. "Keep a leedle off mit your rope—ve don'd vand it to make some drouples for us."

"The air-ship's out of control," the man shouted. "We can't stop the motor and the ship's running away! Grab the rope, hitch it to your automobile and tow us back to South Chicago. We'll give you a hundred dollars for your trouble. Be quick!"

"I like his nerf, I don't t'ink!" growled Carl. "He vants to run off mit us und der pubble, und——"

"We can tow the air-ship, all right," cried Matt, "providing we can get the rope fast to the automobile. We'll have to take a half hitch with the trailing end of the rope around a tree, and bring the air-ship to a stop."

Matt started for the rope. As he bent down to lay hold of it, the car gave a lurch sideways and the rope was whisked out of his hands and was thrown directly against Carl's feet.

Carl grabbed it. At the same moment the air-ship took an upward leap, on account of the weight which Carl had taken off the car. This leap flung Carl into the air. He turned a frog-like somersault, hands and feet sprawled out, and came down with a thump, flat on his back.

"Whoosh!" he yelled, a good deal more startled than hurt, sitting up on the grass and shaking his fist at the bobbing craft overhead, "you dit dot on burpose! Vat's der madder mit you, anyvay? Vat for——"

Carl forgot his fancied grievance watching Motor Matt. The latter, making another leap at the rope as it settled back again after overturning Carl, succeeded in laying hold of it.

He had the rope by the end, so that when he picked it up none of the weight was taken from the ship, and Carl's disastrous exploit was not repeated.

"Wrap it around a tree!" yelled the man at the air-ship's rail; "take a half-hitch around a tree!"

The man might just as well have saved his breath. That had been Motor Matt's plan, all along, and even as the aeronaut was shouting his instructions Matt was jumping for the nearest tree.

The young motorist had little time to make the rope fast. The whirling propeller was driving the Hawk onward against the wind at a fair rate of speed. Had there been no opposing wind, Matt would not have had time enough for the work ahead of him.

"Come on, Carl!" he shouted.

The Dutch boy stopped watching and made haste to lend a hand.

Matt was already at the trunk of the tree, but the rope had traveled onward so rapidly that he had less than a yard of it in his hands to work with.

Throwing himself on the opposite side of the tree, Matt laid back on the end of the rope. At that moment Carl reached his side, dropped near him and likewise took a grip on the free end of the drag.

"It's der fairst time," panted Carl, "dot I efer heluped make some captures mit an air-ship. Shinks! Look at dot, vonce!"

The driving propeller had forced the Hawk to the end of its leash. The boys, with only a half wrap of the rope around the trunk, felt the quick pull, but easily controlled it. The pull was steady, but, inch by inch, they worked more and more of the rope around the trunk until there was enough to make a knot.

"Dot's der dicket!" exulted Carl, scrambling erect. "Ve've got her tied like a pird mit vone foot. Now how ve going to ged her hitched ondo der car?"

"We'll have to find out what's the matter with the motor, up there," answered Matt, "and see if the power can't be shut off."

As he spoke, he got to his feet and walked down the road to a point directly under the air-ship.

CHAPTER II.

A QUEER "FIND."

Both passengers in the air-ship were now leaning over the rail of the suspended car.

"Hitch us on to your automobile," shouted the one who had been doing the driving, "and tow us back to South Chicago."

The offhand way in which the man spoke proved that he was lacking on the practicable side of his nature.

"That's a whole lot easier said than done," Matt called back. "It was only by a happenchance that we got your drag-rope tied to the tree. If you've got an anchor-rope up there, throw it down and we'll make it fast to the car before we cast off the other."

"That's the only long rope we've got," answered the man.

"Well," went on Matt, "you ought to be able