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
Japanese 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 passed 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 disapp