quickened and pulsed with accumulating vibrations.
Again the boy found himself aroused to eager expectancy. There was a
whirl in the air; a crackling like distant musketry; a flash of
dazzling light--and the Demon stood before him for the third time.

"I give you greetings!" said he, in a voice not unkindly.

"Good afternoon, Mr. Demon," answered the boy, bowing gravely.

"I see you have returned safely from your trip," continued the
Apparition, cheerfully, "although at one time I thought you would be
unable to escape. Indeed, unless I had knocked that tube from the
rascally Turk's hand as he clambered to the top of the wall, I believe
you would have been at the Yarkand oasis yet--either dead or alive, as
chance might determine."

"Were you there?" asked Rob.

"To be sure. And I recovered the tube for you, without which you would
have been helpless. But that is the only time I saw fit to interfere
in any way."

"I'm afraid I did not get a chance to give many hints to inventors or
scientists," said Rob.

"True, and I have deeply regretted it," replied the Demon. "But your
unusual powers caused more astonishment and consternation than you,
perhaps, imagined; for many saw you whom you were too busy to notice.
As a result several able electricians are now thinking new thoughts
along new lines, and some of them may soon give these or similar
inventions to the world."

"You are satisfied, then?" asked Rob.

"As to that," returned the Demon, composedly, "I am not. But I have
hopes that with the addition of the three marvelous devices I shall
present you with to-day you will succeed in arousing so much popular
interest in electrical inventions as to render me wholly satisfied with
the result of this experiment."

Rob regarded the brilliant apparition with a solemn face, but made no
answer.

"No living person," continued the Demon, "has ever before been favored
with such comforting devices for the preservation and extension of
human life as yourself. You seem quite unappreciative, it is true; but
since our connection I have come to realize that you are but an
ordinary boy, with many boyish limitations; so I do not condemn your
foolish actions too harshly."

"That is kind of you," said Rob.

"To prove my friendliness," pursued the Demon, "I have brought, as the
first of to-day's offerings this Electro-Magnetic Restorer. You see it
is shaped like a thin metal band, and is to be worn upon the brow,
claspi