spark-plug, but I don'd got der nerf to make a drifer."

Carl had been through experiences about which Matt was anxious to learn, but, for the present, the mystery of the red car claimed his entire attention.

"Why should any one want to cut a car like this adrift?" queried Matt.

"Dat's more as I know," answered Carl, closing the bonnet, "aber led's be jeerful, Matt. Oof fife t'ousant tollars comes rolling indo our hants, all py itseluf, for vy shouldn't ve be jeerful?"

"This car don't belong to us, Carl, just because we happened to stop it."

"Vell, oof you hatn't shtopped it it vouldn't haf peen vort' nodding! Und der feller vat hat it didn't vant it, or he vouldn't haf let it go. So helup me, I t'ink it pelongs py us. I vant to go py Tenver. Vere do you vant to go?"

"I came from Phœnix to Ash Fork, two weeks ago, with a letter of recommendation to a wealthy cattleman who has just bought a big automobile and wants a driver. I had my eye on the job, Carl, but the cattleman hasn't shown up. He lives here, though, and I'm waiting for him. If it wasn't for that, I'd just as soon pull out for Denver, myself."

"I don'd got some money," said Carl, "und along comes der audomopile und say, 'Chump in, boys, und led me dake you py Tenver!' Und I, in der jeerful vay vat I haf, make some remarks aboudt 'Vy nod?'"

Matt went around to the front and began cranking.

"Well, jump in," said he, coming back and getting into the driver's seat; "we're going to start."

"For Tenver?" cried Carl.

"Hardly," laughed Matt, backing away and turning the car in the road; "we're off along the back trail to look for the touring-car's owner."

"Vell, meppy he don'd vant it?"

"Then, if we find him, we'll give him a chance to say so."

"How you t'ink ve vas goin' to find him?"

"This car hasn't been abandoned very long, nor very many miles back on the road. You see, the road is straight for only a few miles, and the car, with the wheel lashed as it was, could only travel along the straight track. If it had been abandoned before it was put on the straight track, it would have been in the ditch."

"You know more in a minit as I in a year know, Matt," said Carl, heaving a long breath, "und dot's all aboudt it. Ve vill look for der owner, und I vill shdill be jeerful efen oof he dakes der car und makes me valk by Tenver, yah, so. It vas some pig mysderies, anyvay; py chimineddy, it vas der piggest vale oof a mysdery vat efer come my vay."

Motor Matt agreed with Carl. Somewhere along the straight stretch of road ahead of them he felt sure the key to the mystery would be found.

And what would it reveal?

CHAPTER III.

THE MAN AT THE ROADSIDE.

Back past Hop Loo's adobe Matt drove the car, and on into the open country. For five or six miles the road ran as straight as an arrow, and was almost as level and smooth as a boulevard. Ahead of them, as they moved forward, the boys could see the marks left by the wheels when the car had passed over the road headed toward town. No other pneumatic tires had left a trail in the dust.

"I bed you somet'ing, Matt," remarked Carl, "dot dis car don'd pelong py Ash Fork."

"There's only one car owned in Ash Fork," said Matt, "and that belongs to the cattleman I came to the town to see. From the looks of the road, no car has come into town or gone out of it for several hours, except this one. Keep a sharp watch on your side of the road, Carl. We've got to find the place where the car stopped while the driver was lashing the wheel and getting out."

"Py shinks, I haf peen vatching as sharp as some veasels, aber I don'd see nodding."

Matt was covering the back trail slowly, so that no clues which might have been left in the road could get away from his keen eyes.

For a long time neither he nor Carl saw anything of importance; and then, suddenly, when they were about four miles from town, Matt's sharp glance showed him something that caused him to bring the car to a quick stop.

"Vat it iss?" asked Carl excitedly.

"Get down and I'll show you," answered Matt.

When they were both in the road, beside the car, Matt pointed to a spot close to the wheel-marks left by the car on its trip into town.

"Py shinks," muttered Carl, pushing his fingers through his carroty hair in a puzzled way, "dot looks schust like some feller had t'rowed a bag der car off. Dose marks in der dust look schust like dey vas made mit some pags."

"It must have been a bag that could move, then," said Matt.

"Huh?" queried Carl, his bewilderment growing.

Matt showed him how the broad mark in the dust had moved toward the roadside.

"And that bag, as you call it, Carl," continued Matt, "wasn't thrown out. If I'm figuring this thing right, it fell out."

"Hoop-a-la!" exulted Carl admiringly, "you vas some Sherlock Holmes, I bed you. How you make dot figuring, anyvay? I know as mooch as you, meppy, oof I could only t'ink oof it. You tell me somet'ing, und den I know."

Matt stepped toward the side of the road opposite from that where the broad, flat mark ran toward the edge.

"You see, Carl," he explained, "this road isn't quite so level here. There's a bit of a ridge, and when the car came into town, the wheels on the left side went over that ridge, tilting the machine to the right. What you call the bag dropped over the right side and into the road."

"Yah, so! Und ven it hit der road it moofed mit itseluf. Funny pitzness. Der furder vat ve go, der less vat ve know, hey? Vat next, Matt?"

"We'll follow the trail and see where it leads."

"Sure! Aber ve don'd vant to go too far avay from der car. Some goot-for-nodding fellers might come along und shnook it on us."

"I don't think we'll have to go very far, Carl."

"Veil, be jeerful. Vatefer ve findt, Matt, schust be jeerful. Oof I can't go py Tenfer in dot car it vill be a plow in der face; aber vatch und see how I took it."

Low bushes lined the roadside. Matt, not paying much attention to Carl's last remarks, was moving off in the direction of the bushes, following the strange broad trail.

Parting the branches at the outer edge of the thicket, he moved into the tangled undergrowth. Carl, who was pushing along behind him, saw him stoop down and disappear below the tops of the bushes. The next moment, the Dutch boy heard a startled exclamation, and Matt straightened up quickly. His face, which he turned toward Carl, had gone suddenly white.

"Come here, Carl!" he called.

"You findt der moofing pag, hey?" asked Carl, floundering through the brush.

Then, a second later, Carl's face also blanched.

Coming close to Matt, and looking down, he saw the form of a man curled up in a little cleaned space in the thicket. The man's hat lay beside him, and about his forehead was tied a blood-stained handkerchief. His face was pallid and deathlike, and his eyes were closed.

"Himmelblitzen!" whispered Carl. "Iss he deadt, I vonder?"

Matt knelt down and laid a hand on the man's breast; then, lifting up one of his limp wrists, he pressed his fingers against the pulse.

"He's alive," said Matt.

"Den it vasn't a pag vat tropped oudt oof der car——"

"It was this man," cut in Matt. "He was sitting in the driver's seat. When the car pitched to the right he was too weak to hold himself in, so he fell into the road."

"Und hurt his head ven he fell!"

"No, he must have hurt his head before he fell. It wasn't so very long ago, Carl, that he took his header from the car, and that bandage must have been around his temples for two or three hours, at least."

"Den vat? Oof he vas too veak to shtay py der car, how he tie der veel like vat it vas?"

"He must have been running the car and steering. Feeling his strength going, he lashed the