This last remark was addressed to the motive power of his jaunty red wagon. In obedience the wheels began to revolve faster. But press onward as he would, supper-time found the professor--so strangely shorn--still some distance from the hills.

"That storm's coming right up, too," he said to himself over his after-supper pipe; "well, no help for it. I guess we'll have to push on."

Watering his animals from a bucket previously filled at the spigot of a big water keg built into his wagon the professor hitched up and pressed on to his destination. Darkness came on, but still he drove steadily forward, seeking the shelter he knew he could find in the lee of the barren hills.

"Going to be a hummer and no mistake," he commented half aloud; "good thing-it-didn't catch me out in the middle of the alkali or Red Bill and his cronies might have had a new lease of life."

It was close upon midnight when the professor found a spot to his liking, and by that time the first desultory puffs of the coming storm were sighing in the nooks and crannies of the barren hills.

He tethered his team, gave them their hay in the shelter of the wagon, watered them and then, after a good-night pipe, prepared to turn in. He woke from a troubled doze to find the wind rocking the wagon within which he slept.

"Wonder what kind of weather the ponies are making of it?" he muttered, and rising he opened the canvas flaps at the front of the wagon and peered out.

At that instant he saw, or thought he saw, two dark objects move by in the flying smother of sand. But the next moment he told himself it must have been imagination.

"Guess being alone so much is getting on my nerve," he commented.

Having seen that his stock were lying down and turning their backs on the flying drift, Wandering William, as he called himself, retired once more. But he couldn't sleep for thinking of the strange illusion he had had.

"No, it wasn't an illusion either," he said stoutly to himself the next instant. "I'm prepared to swear that I really did see two figures on horseback, though what, in great ginger cookies, they were doing out in this I don't know. Appears to me though that they must have had to call a halt right around here some place. In that case I'm going to give 'em a hail, an' if they answer it invite 'em into the wagon. This is no weather to be out without an umbrella."

Chuckling a little at his joke, Wandering William arose and went once more to the front of his wagon.

Placing his hands to his mouth, funnel-wise, he sent a long, shrill cry vibrating out through the storm. Another and another he gave till he was hoa.r.s.e, but there was no reply.

"Guess I was dreaming after all," remarked Wandering William retiring once more to his blanket.

A sickly yellow light struggling through the sand-laden air heralded the day. But the wind had died down and the particles still held in suspension were rapidly thinning out of the air.

Roy thrust his head from under his saddle like a turtle from its sh.e.l.l.

His lips were dry and cracked, his eyes smarted, his skin was irritated with the sand. The whole world seemed to have turned to sand. It was everywhere.

"Peggy!"

A similar turtle-like head projected from the other saddle. Poor Peggy, she would positively have screamed if she had known the appearance she presented. Her hair was tousled, her eyes red with irritation of the sand, and her lips dry and cracked like Roy's.

"Is--is it all over, Roy?" she asked a bit quaveringly.

"I think so. The wind has died down, and look, the ponies have gotten to their feet. I guess they know."

"Wasn't it awful. I never thought we should live through it."

"Nor did I. But there's one good thing, it has obscured our tracks.

If any of Red Bill's gang tried to follow us now they'd have a lot of trouble."

"That's so," agreed Peggy, and then went on to tell Roy of the terrifying screeches and yells she had heard in the night.

"Nothing but the wind," opined Roy, with boy-like superiority. But the next instant it was his turn to start amazedly. Through the fog-like gloom that still overhung the desert a figure was making its way toward them. Roy's hand flew to the revolver with which the thoughtful Ah Sing had provided his saddle holster.

At the same instant the figure, seemingly that of a young man, turned, and wheeling quickly, ran backward and was swallowed up in the obscurity.

"Was that one of Red Bill's men?" gasped Peggy.

"Impossible. They could not have traveled through that storm. But who can it be?"

"What did he run like that for?"

"I'm going after him to find out," declared Roy pluckily; "maybe it's somebody who has become crazed from the sandstorm."

"Oh, Roy, a lunatic!"

Peggy clasped her hands. But the next instant a fresh surprise greeted them. A tall figure with flowing gray locks and gray goatee, topped off with a big sombrero, was seen approaching from the same direction as that in which the youthful figure had vanished.

"Wandering William!" exclaimed the two young adventurers in one breath.

"Yes, Wandering William. The precise individual," was the rejoinder; "and just in time to invite you to breakfast. There, there, no explanations now. You both resemble the output of a threshing machine. But I have mirrors, soap, towels and water in my wagon. Come along, and if you feel ailing, for the insignificant sum of one dollar I will sell you a bottle of Wandering William's Wonderful Wonder Worker."

Exhausted as both boy and girl felt, they could hardly maintain their gravity in the face of this eccentric individual. The very suddenness and utter unexpectedness of his appearance seemed of a piece with his other odd actions. But suddenly Roy recollected the figure that had appeared and then vanished.

"I'd like to accept," said Roy, with vast cunning as he thought, "but what would your partner say?"

"My partner?" Wandering William looked frankly puzzled.

"Yes. That young chap who came toward us and then disappeared again when I came at him with a gun. Not that I blame him," Roy broke off with a laugh, "but I thought for a moment it was one of Red Bill's gang."

Wandering William's keen gray eyes narrowed into two little slits.

"What's that you're saying, boy," he exclaimed; "what do you know about Red Bill Summers?"

"A good deal too much for our comfort," exclaimed Roy, and then he rapidly sketched events of the last twenty-four hours as the trio walked toward Wandering William's wagon.

The strange vendor of medicine seemed to be deeply interested, although he confined his comments to "ums" and "ahs."

"But about that other man," said Roy, returning to the charge when he had finished his narrative, "didn't you see him?"

"My dear boy," said Wandering William seriously, "I think you had better invest in a bottle of Wandering William's Wonder Working Witch Oil for tired and shattered nerves. There is no one in the vicinity but our three selves."

Boy and girl stared at him blankly.

"But I saw him, too," said Peggy.

"I dare say, I dare say," and Wandering William patted his luxuriant curls; "you had a night of strain. What you need is breakfast--hot coffee and all that. Now go in and get fixed up while I attend to your ponies, or rather, Red Bill's."

The wind had by this time died down, and the sun struggled out through the clearing air. n.o.body was in sight but themselves, and fain to believe that their sand-sore eyes must have played them a trick, the boy and girl proceeded to "fix up" in Wandering William's really comfortably appointed wagon.

In the meantime one weight had been lifted from Peggy's mind.

Wandering William had explained that it was he who had uttered the shouts and yells which had so alarmed her in the night.