For more than half an hour eager inquiries were made in Millbrook for a spark plug such as they wanted. But all their search was to no avail. But suddenly, just as they were about to give up in despair, a man, of whom they had made inquiries, recalled that not far out of town there was a small garage.

"We'll try there," determined Jimsy.

Finding out the road, they speeded to the place. It did not look very promising, a small, badly fitted up auto station, run by an elderly man with red-rimmed, watery eyes, looking out from behind a pair of horn spectacles that somehow gave him the odd look of a frog.

"Got any spark plugs?" asked Jimsy, as the machine came to a halt.

"Yes, all kinds," said the man, in a wheezy, asthmatic voice that sounded like the exhaust of a dying-down engine.

"Good!" cried Jimsy, hopping out of the car.

"That is, we will have all kinds next week," went on the man; "I've ordered 'em."

"Goodness, then you haven't any right now?"

"I've got a few. Possibly you might find what you want among them."

"I'll try, anyway," declared Jimsy.

The man led the way into a dingy sort of shed. On a shelf in a dusty corner was a box.

"You can hunt through that," said the man wearily; "if you find what you want wake me up."

"Wake you up?"

"Yes, I always take a sleep at this time of day. You woke me up when you came in. Now I'm going to doze off again."

So saying he sank into a chair, closed his eyes and presently was snoring.

"Dead to the world!" gasped Jimsy; "well, that's the quickest thing in the sleep line I ever saw!"

As it was no use to waste further time the boy began rummaging in the box. It contained all sorts of odds and ends, among them several plugs.

"I'll bet there isn't one here that will fit my engine!" grumbled Jimsy; "I don't—what! Yes! By Jiminy! Eureka! Hurray, I've found one!"

The man woke up with a start.

"What's the matter?" he demanded drowsily.

"Nothing! That is, everything!" cried Jimsy. "I've found just what I want."

"All right. Leave the money on that shelf there. It's a dollar."

So saying, off he went to sleep again, while Jimsy, overjoyed, hastily peeled a dollar from his "roll" and departed. The last sound he heard was the steady snoring of the garage man.

"Well, there's one fellow that money can't keep awake, even if it does talk," said Jimsy laughingly to himself as, with a cry of triumph, he rejoined the party, waving the plug like a banner or an emblem of victory.

No time was lost in starting the auto up again and they whirled back through Millbrook in a cloud of dust. Passing through the village they retraced their way along the road by which they had come.

"Just half an hour before that altitude flight," remarked Jimsy to Roy, who was driving, as they sped through the town.

"Fine; we'll make it all right," was the rejoinder. Roy turned on more power and the auto shot ahead like some scared wild thing.

"We'll only hit the high spots this trip," declared Roy, as the machine plunged and rolled along at top speed.

All at once, as they turned a corner, they received a sudden check. Right ahead of them a man was driving some cows. Roy jammed down the emergency brake, causing them all to hold on for dear life to avoid being pitched out by the sudden change of speed.

"Wow! what a jolt!" exclaimed Jimsy; "it sure did——"

The sentence was never completed. The auto gave a pitch sideways and then plunged into a pit that had been dug across the road and covered with leaves and dust placed on a framework of branches. Down into this pit crashed the machine with a sickening jolt. The girls screamed aloud in fear. It appeared as if the machine would be a total wreck.

But that was not the worst of it. In the sudden fall into the pit Roy had been pitched out and now lay quite still at the roadside. Jimsy had saved himself from being thrown by clutching tight hold of the seat.

He stopped the engine and then clambering out of the car hastened to Roy's side. To his delight, just as he reached him, Roy sat up, and although his face was drawn with pain he declared that his injuries consisted of nothing more serious than a sprained ankle.

"But look at the machine!" cried Jimsy; "it's smashed, I'm sure of it."

The pit which had been dug across the road was about three feet deep and the front wheels of the auto rested in it. The hind wheels had not entered, as the excavation was not a wide one.

Both boys hastened to examine the car. To their satisfaction they found that not much damage had been done beyond a slight wrenching of the steering gear. This was due to the fact that they had been going at reduced speed.

"Gracious! Suppose we had been coming along at the same pace we'd been hitting up right along," exclaimed Jimsy.

"We wouldn't be here now," declared Roy; "we'd be in the next county or thereabouts."

"Yes, we'd have kept right on going," agreed Jimsy; "talk about flying! But, say, who can have done this?"

"Not much doubt in my mind it's the work of that outfit of Kelly's. He told us to look out for trouble, and he appears to be making it for us."

"The precious rascal; he might have broken all our necks."

"That's true, if we'd been hitting up high speed."

"How are we going to get out of this?"

Peggy asked the question just as the man who had been driving the cattle came running up.

"What's the trouble?" he asked, gazing at the odd scene.

"You can see for yourself," rejoined Roy; "some rascals dug a trench across the road so as to wreck our machine if possible."

"Humph! So I see," was the rejoinder; "how be you goin' ter git out of thar?"

"That's a problem. If we could get a team of horses——" The man interrupted Roy, who was acting as spokesman.

"Tell you what, two of my cattle back thar are plow oxen. I'll go back to ther farm, git their yokes on 'em and yank you out of here. That is pervidin' you pay me, uv course."

"Don't worry about that. We're willing to pay anything in reason."

"All right, then, I'll hook up Jeb and Jewel."

The man walked back toward his cattle, which were contentedly browsing at the side of the road. Clucking in an odd manner, he drove two of them out of the herd and started back toward a farmhouse which was not far distant. In a wonderfully short time he was back with his oxen in harness.

"Gee, Jeb! Haw, Jewel!" he cried, as he came up. The oxen swung round and the heavy chain attached to their yoke was hitched to the front axle of the car.

"Now for it!" cried Roy, when this had been done.

"Git ap!" shouted the man.

The slow but powerful oxen strained their muscular backs. The chain tightened and the next moment the car, from which Peggy and Jess and Bess had alighted, rose from the pit. Then the hind wheels dropped into it with a bump, but the shock absorbers prevented serious damage. With the oxen straining and pulling it was finally hauled into the road and they were ready to resume the trip.

Roy rewarded their helper with a substantial bill, and they were all warm in their thanks.

"'Twasn't nuthin'," declared the man, "an' now I guess I'll go to ther house and have my hired man fill in this road. Things is come to a fine pass when such things kin happen."

As the rescued party sped on toward the aviation field they fully agreed with the rustic's opinion. Had it not been for sheer luck they would have suffered extremely serious consequences as the result of a rascal's device. But as it was Kelly's plot against them appeared to have failed.