Fogg started for home. Clark rode with Ralph on the locomotive to the roundhouse. The big engine was put into her stall. Then the boys left the place.

"I have something to say to you, Fairbanks," began Clark.

"I suppose so," replied Ralph. "It must be quite a long story, though."

"It is," admitted his companion.

"Then suppose we leave its recital till we are rested a bit,"

suggested Ralph. "I want you to come up to the house and have supper.

Then we'll adjourn to the garden and have a quiet, comfortable chat."

"That will be famous," declared Clark. "Say, you don't treat an imposter like myself courteous or anything, do you?"

"Are you really an imposter?" asked Ralph, with a faint smile.

"I am--and a rank one."

"Just one question--you are not the real Marvin Clark?"

"No more than yourself."

"And you are Fred Porter?"

"That's it."

"I thought so," said the young engineer.

CHAPTER XV

"THE SILVANDOS"

"I declare!" exclaimed Ralph Fairbanks.

"For mercy's sake!" echoed Fred Porter.

Both stood spellbound just within the grounds of the Fairbanks' home, where they had arrived. Over towards the dividing lot line of the next door neighbor, their eyes had lit upon an unusual and interesting scene.

Two figures were in action among the branches of the great oak tree.

They were boys, and their natural appearance was enough to attract attention. They were leaping, springing, chasing one another from branch to branch, with a remarkable agility that made one think of monkeys and next trained athletes.

"Who are they, anyway?" demanded Fred.

"They are new to me," confessed the young engineer.

The two strangers were about of an age, under sixteen. It would puzzle one to figure out their nationality. Their faces were tawny, but delicate of profile, their forms exquisitely molded. They suggested j.a.panese boys. Then Ralph decided they more resembled lithe Malay children of whom he had seen photographs. At all events, they were natural tree climbers. They made the most daring leaps from frail branches. They sprung from twigs that broke in their deft grasp, but not until they had secured the purchase they aimed at in the act to send them flying through the air to some other perilous point in view.

Their feats were fairly bewildering, and as one landed on the ground like a rubber ball and the other chased him out of sight in the next yard, Ralph conducted his companion into the house with these words:

"That's odd enough to investigate."

He did not announce his arrival to his mother, but led Fred up to his room. As he pa.s.sed that now occupied by the Foggs, it made his heart glad to hear the fireman crowing at the baby to the accompaniment of a happy laugh from the fireman's wife.

"You can wash up and tidy up, Porter," he said to his friend. "I'll arrange for an extra plate, and take you down later to meet the best mother in the world."

"This is an imposition on you good people," declared Fred, but Ralph would not listen to him. He went downstairs and out the front way, and came around the house looking all about for some trace of the two remarkable creatures he had just seen. They had disappeared, however, as if they were veritable wood elves. Pa.s.sing the kitchen window, the young engineer halted.

"h.e.l.lo!" he uttered. "Zeph Dallas is back again," and then he listened casually, for Zeph was speaking to his mother.

"Yes, Mrs. Fairbanks," Ralph caught the words, "I'm the bad penny that turns up regularly, only I've got some good dollars this time. On the mantel is the money I owe Ralph for the clothes he got me."

"But can you spare the money?" spoke Mrs. Fairbanks.

"Sure I can, and the back board, too," declared Zeph, and glancing in through the open window Ralph noted the speaker, his fingers in his vest armholes, strutting around most grandly.

"I can't understand how you came to get so much money in two days,"

spoke the lady. "You couldn't have earned it in that short s.p.a.ce of time, Zeph."

"No, ma'am," admitted Zeph, "but I've got it, haven't I? It's honest money, Mrs. Fairbanks. It's an advance on my wages--expense money and such, don't you see?"

"Then you have secured work, Zeph?"

"Steady work, Mrs. Fairbanks."

"What at, Zeph?"

"Mrs. Fairbanks," answered the lad in a hushed, mysterious tone of voice, "I am hired as a detective."

"You're what?" fairly shouted Ralph through the window.

"h.e.l.lo! you here, are you?" cried Zeph, and in a twinkling he had joined Ralph outside the house. "Yes, sir," he added, with an important air that somewhat amused Ralph, "I've landed this time. On both feet. Heart's desire at last--I'm a detective."

Ralph had to smile. He recalled the first arrival of honest but blundering Zeph Dallas at Stanley Junction, a raw country b.u.mpkin.

Even then the incipient detective fever had been manifested by the crude farmer boy. From the confident, self-a.s.sured tone in which Zeph now spoke, the young railroader was forced to believe that he had struck something tangible at last in his favorite line.

"What are you detecting, Zeph?" he inquired.

"That's a secret."

"Indeed--and what agency are you working for--the government?"

"That," observed Zeph gravely, "is also a secret--for the present.

See here, Ralph Fairbanks, you're guying me. You needn't. Look at that."

With great pride Zeph threw back his coat. It was to reveal a star pinned to his vest.

"Yes," nodded Ralph, "I see it, but it doesn't tell who you are."