THE START.

The following morning dawned clear, and bright, and still. It was a day made to order, so far as aËroplane flying was concerned.

Matt and his cowboy chum spent the night at the post. Before turning in, Matt got into sou'wester, slicker, and rubber boots and churned his way down to the aËroplane tent to see how Ping and the machine were getting along.

Everything was all right, and the heavy, water-proofed canvas was turning the rain nicely. Ping was in love with the Comet, and could be counted on to guard it as the apple of his eye.

"As fine a morning for your start as one could wish for," observed Cameron, with a note of regret in his voice, as he, and Matt, and McGlory came out of the mess hall and started along the board walk that edged the parade ground.

"I'm sorry, old chap, we can't take you with us," said Matt, "but the Comet is hardly a passenger craft, you know."

"What will you do with Prebbles, if he's well enough to go?"

"We'll let Ping come with you by train. Prebbles doesn't weigh much more than the Chinaman."

"Suppose Prebbles doesn't care to risk his neck in the machine?"

"I don't think he'll make any objection. However, we'll go to your quarters and make sure of that, right now. How did he pass the night?"

"Slept well, so O'Hara said. He was still sleeping when a private relieved the sergeant. McGlory," and here the lieutenant turned to the cowboy, "do you feel as much like flying, this morning, as you did last night?"

"Not half so much, Cameron," answered McGlory, with a tightening of his jaws, "but you couldn't keep me out of that flyin' machine with a shotgun. If we join a circus as air navigators, I've got to get used to flying, and I might as well begin right now."

"All right," answered the disappointed lieutenant, "I'll go by train."

The doctor was with Prebbles when Cameron and the boys reached the lieutenant's quarters. What is more, the doctor's face was graver than it had been the preceding afternoon. The old man was throwing himself around on the bed and muttering incoherently.

"Delirious," said the doctor, examining a temperature thermometer; "temperature a hundred and three, and he's as wild as a loon. Newt, Newt, Newt—that's the trend of his talk. You can't understand him, now, but he was talking plain enough when I got here."

"Is the sickness serious?" asked Matt.

"Pneumonia. Know what that is, don't you, Matt? It's hard enough on a person with a good constitution, but in a case like this, where the powers of resistance are almost exhausted, the end is pretty nearly a foregone conclusion. However, we're taking the trouble right at the beginning, and there's a chance I may break it up."

"Get a good nurse for him," said Matt, "and see that he gets all the care possible. The poor old chap was a good friend of mine, once, and I'll bear all the expense."

"Never mind that, Matt," spoke up Cameron. "If Murgatroyd is caught, because of the tip he gave us, the government will be owing Prebbles a lot of money."

Suddenly the old man sat up in bed, his eyes wide and staring vacantly, his arms stretched out in front of him and his hands beating together. His voice grew clear and distinct, echoing through the room with weird shrillness.

One verse was all. Spent with the effort, Prebbles dropped back on the pillow and continued his whispered muttering.

"It's one of those Salvation Army songs," observed the doctor.

"He thought he was marching and playing the cymbals," said Matt, in a low tone.

"Too bad!" exclaimed McGlory, shaking his head.

"Do all you can for him, doctor," urged Matt.

"I will, of course," was the answer, "but you may be able to do more for him than any one else, Matt."

"How so?"

"Why, by bringing back that scalawag son of his. That's the one thing the old man needs. If we can show Prebbles the boy, and make him realize that he's here, and sorry for the past, it will do a world of good."

"I'll bring him!" declared Matt, his voice vibrant with feeling. "Prebbles said this business would make or break him; and, as the work is on my shoulders now, it's make or break for me. Come on, Joe!"

He turned from the room, followed by McGlory and Cameron. Out of the post went the three, and down the hill and past the post trader's store, the king of the motor boys saying not a word; but, when the shelter tent was in sight, he turned to his companions.

"It's mighty odd," said he, "how chances to do a little good in the world will sometimes come a fellow's way. Through that rascal, Murgatroyd, I was led into giving a helping hand to Mrs. Traquair; and here, through the same man, I've a chance to help Prebbles."

"And you can bet your moccasins we'll help him," declared McGlory, "even though we lose that circus contract. Hey, pard?"

"We will!" answered Matt.

Ping had cooked himself a mess of rice on a camp stove near the shelter tent. He was just finishing his rations when the boys and the lieutenant came up.

"We're going out in the aËroplane to-day, Ping," announced Matt.

"Allee light," said the Chinaman, wiping off his chop sticks and slipping them into his blouse.

"You and McGlory are going with me," went on Matt.

The yellow face glowed, and the slant eyes sparkled.

"Hoop-a-la!" exulted Ping. "By Klismus, my likee sail in Cloud Joss!"

"I wish I had that heathen's nerve," muttered the cowboy. "It's plumb scandalous the way the joy bubbles out of him. All his life he's been glued to terra firma, same as me, but, from the way he acts, you'd think he'd spent most of his time on the wing. But mebby he's only running in a rhinecaboo, and will dive into his wannegan as soon as we're ready to take a running start and climb into the air. We'll see."

"Pump up the bicycle tires, Joe," said Matt. "Get them good and hard. Ping," and Matt pointed to the haversack of provender McGlory had brought from the post, "stow that back of the seat on the lower wing. We may be gone two or three days."

"And mebby we'll be cut off in our youth and bloom and never come back," observed McGlory, grabbing the air pump. "This is Matt's make and break," he grinned grewsomely; "we make an ascent and break our bloomin' necks. But who cares? We're helping a neighbor."

Ping crooned happily as he set about securing the haversack. He'd have jumped on a streak of chain lightning, if Matt had been going along with him to make the streak behave.

The Comet had two gasoline tanks, and both of these were full. The oil cups were also brimming, and there was a reserve supply to be drawn on in case of need.

Matt went over the machine carefully, as he always did before a flight, making sure that everything was tight and shipshape, and in perfect running order.

Even if anything went wrong with the motor, and the propeller ceased to drive the aËroplane ahead, there would have been no accident. The broad wings, or planes, would have glided down the air like twin parachutes and landed the flyers safely.

Cameron, having manfully smothered his disappointment, lent his hearty aid in getting the boys ready for the start. The machine, at the beginning of the flight, had to be driven forward on the bicycle wheels until the air under the wings offered sufficient resistance to lift the craft. A speed of thirty miles an hour was sufficient to carry the flying machine off the ground and launch it skyward.

But there was disappointment in store for the boys. The three, seated on the lower plane, Matt at the levers, tried again and again to send the machine fast enough along the muddy road to give it the required impetus to lift it. But the road was too heavy.

The trick of fortune caused Ping to gabble and jabber furiously, but McGlory watched and waited with passive willingness to accept whatever was to come.

"I guess you'll have to give up, Matt," said Cameron. "The road's too soft and you can't get a start."

Matt looked at the prairie alongside the road. The grass was short, and the springy turf seemed to offer some chance for a getaway.

"We'll try it there," said he, pointing to the trailside. "Give us a boost off the road, Cameron, and then start us."

The lieutenant assisted the laboring bicycle wheels to gain the roadside, and then pushed the machine straight off across the prairie. Matt threw every ounce of power into the wheels.

Usually the air ship took to wing in less than a hundred yards, but now the distance consumed by the start was three times that. For two hundred feet Cameron kept up and pushed; then the Comet went away from him at a steadily increasing pace. Finally the wheels lifted.

Quick as thought, Matt shifted the power to the propeller. The Comet dropped a little, then caught herself just as the wheels were brushing the grass and forged upward.

"Hoop-a-la!" cried Ping.

McGlory said nothing. His face was set, his eyes gleaming, and he was hanging to his seat with both hands.