passage entrance, as though they were expecting the arrival of some one
or something.

Suddenly came a dull metallic clank through the passage, strangely
echoing. At once all leaped to their feet, at attention, not unmixed
with awe and fear that sat strangely on their desperate features. What
was it that they, who feared neither God nor man, feared?

They strained their eyes, looking into the passage that led darkly away
into blackness.

Dimly down it now could be seen two gleaming spots of light, points in
the Cimmerian darkness. They seemed to be growing larger and coming
nearer as with each hollow reverberation the dull metallic thuds
increased.

Faintly now could be made out in the blackness a huge, stalking figure,
having the shape of a man, with gigantic, powerful shoulders, powerful
arms, a thick body, hips, and thighs that spelled terrific strength,
legs and feet that suggested irresistible force.

"The Automaton!" escaped involuntarily from all lips.

Slowly, irresistibly, the horrendous figure stalked forth into the dim
light. There it paused for a moment--a figure of steel, larger than most
men, yet not so large but that it might have incased a man. And yet its
motions, its every action, were like nothing mortal. Even these hardened
denizens of the underworld shuddered.

In its hand the Automaton carried a five-branched candlestick, for what
purpose none seemed to know. Yet all bowed and quaked at every pantomime
motion of the figure, ready to do the bidding of the least motion of
their inhuman master.

Still holding the candlestick with its five huge yellow candles before
him, the Automaton stalked forward to the table and impressively
deposited the candlestick on it, then stepped back a pace and waved his
ponderous hand at the assembled emissaries, who scarcely repressed their
own abject terror.



CHAPTER IV


At a motion from the Automaton a dark-skinned Madagascan stepped forward
and lighted the five candles. At once a dense smoke began drifting from
the candles.

The men looked at one another, showing an uncomfortable fear of what the
negro and the Automaton were doing. Even the negro edged away fearfully
and all crouched back, afraid of the fumes.

A moment later the Automaton, with a mighty blast of air, snuffed all
the candles at once, then, without a word, picked up the candlestick and
stalked off through the passage on the opposite side of the den from the
entrance, the passage that led to the Graveyard of Genius.

A few moments later the secret rock door from this passage into the
Graveyard swung open and the Automaton stalked in, going carefully,
noiselessly, now. Across the floor he walked to the steel door, which he
swung open, then on out into the cellar of Brent Rock and up the steps
to the door under the stairs that led to the hallway of the great house.

In the hall the Automaton halted beside a small stand on which stood a
candlestick exactly like the one he carried. Quickly he picked up the
original candlestick and replaced it by the one he carried. Then he set
the original back of the portieres, and with a glance at the library
door turned back to the cellar, closing the door noiselessly behind him.

Down the steps he went, toward the open door of the Graveyard of Genius.
Beside the door was the fuse-box of the lighting system of the house.

The Automaton reached out and began rubbing sharply at the insulation of
the feed wires.

Up-stairs, in the dining-room, Brent had by this time flung off his coat
and was examining with Flint the curious model the adventurer had
brought from Madagascar. Brent was very excited and questioned Flint
eagerly.

"I tell you, Flint," cried Brent, at length, huskily, as he seized a pen
and dipped in into the ink, "the time has come for me to do what I have
long intended. I am going to do now what I should have done years ago."

Brent started to write feverishly:

QUENTIN LOCKE,--I have done you a great injury about which you know
nothing, but I am willing to--

His hand had scarcely traced the last word when the room was plunged
into absolute darkness.

Down in the cellar the Automaton had succeeded in rubbing off the
insulation of the feed wires. There was a flash of light as he laid his
steel hand over the two feed wires--then darkness.

In the dining-room Brent and Flint, already keyed to the highest pitch,
leaped to their feet with an exclamation of terror.

Late as it was, Locke was working in his laboratory on the second floor
of the house when the lights winked out. Surprised for the moment, he
ran out into the hall.

Already there was the butler, groping about with a candle.

"What's the matter, Quentin?" asked a breathless voice behind them.

It was Eva in a filmy dressing-gown. Locke turned to vision a creation
of loveliness in the candle-light which set his heart thumping.

"Nothing," he reassured. "Just the lights short-circuited, that's all.
I'll see."

Just then the dining-room door opened and Eva saw her father, disheveled
and preoccupied, stride out and take the five-branched candlestick from
the hall table. Nervously he began to light the candles. They sputtered
a bit and he turned quickly, still holding the candlestick, as the smoke
drifted away from them all.

"Fix the fuses in the cellar," he directed the butler.

"Is anything--really the matter--father?" implored Eva.

"No, no, my child," he answered, hastily. "Go back to bed. And, Locke,
please don't let us be disturbed."

He was about to say more, then decided not to do so, and turned back
into the dining-room.

Again Brent carefully locked the door to the dining-room and rejoined
Flint.

He had placed the candles on the table, not noticing in the half-light
that the smoke from them was growing denser as they burned down.

The smoke drifted over as the draught carried it. Flint coughed and
moved a bit, his hand at his throat.

Brent seized the pen again and was about to write, when the smoke from
the candles drifted into his own face. He, too, coughed.

Uneasy, Brent glanced over at Flint. Flint laughed, a bit hysterically.

"What the devil's the matter?" demanded Brent, with lowered brows, a
strange dryness in his throat.

Flint was now leaning forward on his elbows and laughing foolishly,
stupidly. It was a queer laugh, and struck terror into Brent as he
himself coughed and clutched involuntarily at his throat. Brent stared
at Flint.

"What is it?" he repeated, anxiously. "Have you suddenly gone mad, man?"

But there was no reply. Instead, Flint laughed all the more madly.

Brent was more than startled. If he could have seen himself in a glass
he would have seen that he was already wide-mouthed and disheveled.
Suddenly the smoke again blew in his face. He coughed again. His head
reeled.

Then, in a flash, it all dawned on him.

He shielded himself from the candles. But it was too late.

"My God!" he exclaimed, starting up. "The Madagascar madness!"

Brent looked about wildly. He rushed to Flint and shook him. But Flint
only laughed. He turned and moved toward the candles, reaching out for
them. But even as he did so his hand faltered.

He stopped and passed his hand across his tightening forehead. Slowly
over his face came a stupid expression. He felt himself going, without
power of retraining himself. His lips twitched and he swayed.

Then he began to laugh uncontrollably.

Flint rose and clapped him on the shoulder. Then both laughed foolishly,
loudly.

They were beyond help. It was the laughing madness.

Outside, in the hall, Eva and Locke had been standing, talking for a
moment, when suddenly, below, they heard a terrific noise in the cellar.
Involuntarily Eva's hand clutched Locke's arm. Locke drew a revolver
and, in spite of Eva's fearsome caution, hastened down the cellar
stairs.

About in the blackness of the cellar he groped until his foot touched
something soft, a mass on the floor. He bent over. It was the butler, in
a heap, unconscious, but still breathing.

There was not a sound, not another being in the cellar.

Together Eva and Locke helped the now half-conscious man to his feet and
pushed and pulled him up the stairs; as slowly he recovered his power of
speech.

"What was it--tell us?" urged Locke.

"I--I went down to fix the fuses--as the master ordered," muttered the
butler, incoherently. "A huge figure--steel hand--it flung me across the
floor--the last I remember."

He passed his hand over his head as though recollection even was too
horrible for description.

Locke listened a bit doubtfully, then sent the butler on his way to bed,
while Eva could scarcely restrain her fears.

Over to the dining-room door Locke strode and listened. There was
nothing but the sound of merriment inside, of uncontrollable laughter.
Could it be that Brent and Flint were drinking? He dared not betray a
fear to Eva. Instead he knocked.

At that moment he could hear the sound of some heavy body falling; then
more laughter as Brent in his hysteria struck the model of the automaton
to the floor.

With the model, unnoticed by Brent, now fluttered to the floor the
letter he had been writing. But the madman paid no attention to that now
as it sifted through the air and fluttered under the sideboard.

"Mr. Brent," called Locke, "please open the door."

Instead of an answer came a loud and insulting laugh, followed by an
incoherent mouthing of words. Eva looked startled, blanched. It was so
unlike her father. For the moment Locke was piqued. But he tried not to
show it as he turned away from the door.

"I am your father's employe," he said, sadly, "and it is his privilege,
I suppose, to laugh at me." He hesitated.

"Oh, but, Quentin--Mr. Locke--I'm--I'm so sorry. Surely he could not
have meant it."

At the head of the stairs Locke tried to smile.

"Don't worry," he said, repressing his feelings. "It will make no
difference between us. Good night."

They parted, Eva closing her door for a sleepless night, Locke to work
far into the night in his laboratory until sheer exhaustion overcame his
feelings.

Meanwhile, in the dining-room, the two men kept terrible vigil, hour
after hour, oblivious of time, in wild and wanton laughter--maniacal
abandon.

A terrible blow had been struck and Reason was tottering on her throne.

Two men had been stricken by an unknown hand--stark, stark mad.



CHAPTER V


"Father--please--open the door!"

It was early the following morning that the butler with frightened face
had called Eva Brent to tell her that her father and Flint had been
locked in the dining-room all night and were still laughing madly.

Eva had hurried down-stairs, encountering Zita as she ran. It was true.
She could hear the voices inside. Nor could she get any answer from the
two men.

"Oh--Zita--please--can't something be _done_?" Eva implored.

With a hasty word Zita hurried away just as Herbert Balcom himself
entered the house from the street.

In utter surprise Balcom nodded at Zita as she poured forth the story of
what had been discovered in the morning, then pushed past her in high
excitement.

"What's wrong?" he asked as he came upon the butler and Eva still
knocking excitedly at the dining-room door.

Eva was almost in a panic as she answered, "Father and Mr. Flint have
been in there laughing ever since last night."

Balcom tried to comfort her. But somehow his sympathy sent a cold
shudder through the poor girl.

Meanwhile Zita had encountered Locke hurrying down at the sound of the
commotion. To him she told the story, again hurt that his interest was
solely for Eva, not in herself.

Locke paused long enough to seize an umbrella from the rack, rip the
cover off, and break out a rib, to which he tied a piece of string while
he hurried to the group at the door.

"Break down the door and call the police," ordered Balcom.

The butler reached for a chair and was about to swing it over his head
to break down the door.

"Stop!" interrupted Locke.

The young scientist knelt down, inserted the umbrella steel through the
keyhole, and bent it by the string as he fished about with it on the
other side to find the bolt. Meanwhile the butler telephoned frantically
for the police.

It was at this height of excitement that Paul Balcom entered. A moment's
talk with Zita, and he, too, joined the group.

Sympathetically he spoke to Eva, but Eva scarcely responded in the
fashion of a girl to the man whom she was going to marry. Her attention
was riveted on Locke, who was kneeling before the door. Paul saw it and
an ominous scowl crossed his face.

Carefully Locke worked the umbrella steel and the string until he had
caught the bolt. Then he shot the bolt back and rose to his feet. All
watched him expectantly as he threw open the door.

Such a sight as met their eyes one could scarcely picture.

There were Brent and Flint at the table--laughing--laughing. The candles
had long since burned out. On the floor lay the automaton model.

"Father!" cried Eva, running to him.

But there was no look of recognition on Brent's face.

"Don't you know me? Speak to me! Father!"

Instead, Brent merely patted her shoulder and laughed hollowly. Eva, on
her knees by him, sobbed and smoothed his head by turns.

Locke, bending over Flint, found him in much the same condition.

Meanwhile, Balcom and Paul had picked up the model of the automaton and
exchanged a quick glance.

"This man Locke's actions are suspicious," exclaimed Balcom, hastily.
"He was in the house last night."

Outside they could hear the arrival of the detectives summoned by the
butler.

"Go to Eva," nudged Balcom to Paul.

A moment later the butler entered with the detectives.

At the sight of the automaton model in Balcom's hands the butler cried
out:

"That is what attacked me last night--only larger--much larger!"

All eyes were now on the butler. Quickly Balcom took advantage of the
situation thus created. Locke, also, left Flint and moved over to the
group examining the model. As he did so his eye caught a piece of paper
under the sideboard. He was about to pick it up when he realized that
all were looking at him. Quickly he covered his discovery and faced
them.

"This man is the stranger in the house," cried Balcom, in anger. "Arrest
him and make him explain."

It was the work of only an instant for the chief detective to step up to
Locke and slip the bracelets on his wrists.

"Don't!" cried Eva.

"Please--my dear--your father," remonstrated Paul.

At that instant Brent was seized with another violent fit of coughing
and laughter. Eva, distracted, was half fainting.

Thus, with Locke handcuffed, Balcom and Paul were triumphant.

Locke saw his chance. But the handcuffs prevented him from using his
hands. In the instant that all were diverted toward Brent, with
incredible deftness Locke slipped his hand from the cuffs, one link of
which fell open as if by magic, through a secret all his own. He reached
down and picked up the paper under the sideboard and read it. It was the
letter Brent had been writing and served only to increase his
perplexity. He read it again, then crushed it into his pocket, and
before any one had discovered his trick had slipped his hand back into
the cuffs and they were locked again.

At that very moment the telephone rang and the chief of the detectives
answered. As he did so a perplexed expression crossed his face and he
walked over quickly to Locke.

"I--beg your pardon," he apologized as he began to unlock the handcuffs.

"Here, my man, what are you doing?" interrupted Balcom.

"I know my business. You lay off," growled the detective.

A moment later Locke, with a slight smile on his handsome face, was
answering the telephone.

Not a soul save the detective, even yet, suspected the true identity of
Locke, even as he answered over the telephone with a respectful, "Yes,
sir."

The fact of the matter was that the message had come most opportunely.
It was from the chief of the Department of Justice himself, ordering
Locke to stay at the house until he had secured the evidence that would
allow the department to proceed against the company under the anti-trust
law. That, then, was the explanation of the secret dictagraph which
Locke had installed, the explanation of his apparent faithlessness to
his employer.

But weightier matters were now on Locke's mind. Here he was faced by the
case of his life, involving the happiness of the very girl whom he had
so soon come to love. His incentive was double--love and success:
triple--above all, justice.

By this time the household themselves were sufficiently calm to help
Brent to his bedroom and Flint to a guest-chamber.

Balcom was about to follow, when Locke, returning from the telephone,
touched him on the shoulder and shoved the threat message which Brent
had given him the night before under the face of the junior partner.

"Read that," he demanded.

Balcom read, controlling his features admirably, if control were
necessary.

"What's the meaning of this?" he demanded, coldly.

"Were you in Madagascar lately?" shot back Locke.

Locke could not be sure whether or not Balcom suppressed a start. At any
rate, he did not conceal anger at the insinuation.

"Certainly," he replied. "With my son I cruised through the Mozambique
Channel and touched at Madagascar last summer. Why?"

Locke nodded and the detective made a note of the reply.

"What do you mean to insinuate by that question?" demanded Balcom.

Without reply Locke shrugged nonchalantly and smiled.

Not ten feet away, in the conservatory door, Paul listened, and his face
darkened as he clenched his fists.

There was a murderous glare in Paul's eyes as Locke unconcernedly
withdrew, whispering to the detective, who nodded deferentially to the
young scientist who had been assigned by the Department of Justice,
strangely, to the very case which now he realized in some unknown way
must concern himself and the very mystery of his own identity.

So wore along the morning, with growing mystery and excitement.

It was not long before the Brent family physician was summoned, and
after a careful diagnosis pronounced Brent in a hopeless state as far as
his own science was concerned. Eva was by this time more than frantic.
The consolation of Paul seemed to add to her nervousness. She was almost
distracted when she heard Balcom and the doctor discussing the case in
low tones in her father's room.

"Don't you think, Doctor," she overheard, "that he would be far better
off in a sanitarium?"

She shuddered as the doctor agreed with Balcom, and Balcom sought to
persuade her that the course was best. Even the solicitations of Paul
annoyed her. Paul was more than vexed at this new repulse from his
bride-to-be. His anger knew no bounds as he caught sight of Locke, who
had overheard and showed his doubt over the whole proposal for the care
of Brent. He plucked at his father's sleeve and nodded toward Locke.

Balcom needed no prompting from his crafty son.

"I'll have you understand, Locke," he cried, his face growing apoplectic
red, "that I am in charge here now. Your services are no longer
required."

"I quite understand," returned Locke, quietly. "We shall see."

Balcom stormed down from the room to the telephone, where, a moment
later, he telephoned to an asylum, asking them to send a conveyance with
nurses, keepers, and whatever paraphernalia was necessary to take care
of his partner, Brent.

"Is he violent?" demanded the doctor over the telephone.

"Yes. Bring a strait-jacket," snapped back Balcom. "And the sooner he is
under your care the better."

With that Balcom stamped out of the house.

In Brent's room, Paul was attempting still to ingratiate himself with
Eva, who was growing more distant toward him with every moment. Finally
Paul could stand it no longer. He turned on his heel and faced Locke
angrily in the hall.

"You'll regret this, confound you!" he ground out, as he swung out of
the room rapidly in a high state of feeling.

Unconcernedly Locke turned on his heel.

"Don't worry," he whispered to Eva. "I'll see that no harm comes to your
father."

For answer, her own heart too full for words, Eva pressed the hand of
the young scientist. It was reward enough for Locke.

Meanwhile, at Doctor Shaw's sanitarium, to which Balcom had telephoned
with the permission of the doctor, elaborate preparations had been
completed for the reception and transportation of Brent.

It was perhaps an hour later that the ambulance, with three
white-uniformed attendants, pulled out, carrying all those appurtenances
necessary for the care of the insane, including the strait-jacket which
Balcom had so testily suggested.

That same hour had seen intense activity in another quarter. In the den
of the Automaton, the hard-visaged emissaries had been already roused by
the entrance of the Automaton.

Hasty directions had been uttered by the metallic, phonograph voice of
the monster, and already four of the most desperate of the characters
had hurried through the entrance out on the cliffs. The Automaton
himself had turned toward the passage through the Graveyard of Genius to
Brent Rock itself.

Thus it happened that when the ambulance from Doctor Shaw's sanitarium
came bowling along the road to Brent Rock as fast as its motor would
permit, the driver was forced suddenly to put on the brakes to save
himself from being wrecked by a huge log that lay squarely across the
road.

No sooner had the attendants jumped out to remove the log than four
desperate men fell upon them from ambush, beat them, and left them
trussed up and unconscious, while they donned the jackets and uniforms
of Doctor Shaw's men, seized the ambulance, and swung off again at a
fast clip in the direction of Brent Rock.

Lulled into a false security, as her father slept now for a time under
an opiate, Eva was sitting beside him with loving care when she heard
the noise below of the arrival of the car from Doctor Shaw's sanitarium.
At once she was in wild alarm. Nor was Locke off his guard. While Zita
tried to reassure Eva, Locke met the men.

There were four of them, and as the first passed, Locke halted him. The
parley gave another a chance to push past, while Locke held three at
bay.

A moment later there was a scream from Eva, who had hurried from her
father's room at the sound of the high voices. The emissary had seized
her.

It was a signal for the other three, who leaped on Locke all at once.
With almost superhuman strength Locke seized one of them and flung him
over his head for a fall down the whole flight of steps as he fought the
other two single-handed.

Even then the third came back to the attack and Locke was forced to give
back step by step down the stairs.

Another scream from Eva.

In the heat of the fray Locke caught a glimpse of her battling on the
landing above with the first emissary. It gave him redoubled strength.

Flinging the two men off and eluding the third, he leaped to the
chandelier in the hall and with a giant swing wrapped his legs about the
fellow struggling with Eva. Literally throttling him, he pulled him
backward over the balcony railing for a fall clear to the lower hall.

At the moment when Locke was actually subduing all of his assailants the
door to the cellar suddenly opened and the huge figure of the Automaton
strode out.

With one blow of his steel fist the monster struck Locke senseless, then
turned and began ascending the grand staircase.

Almost paralyzed with fear, Eva screamed again and fled through the
nearest door, locking it. On strode the Automaton, crashing down the
door as if it had been a mere shell.

Meanwhile the emissaries had seized Locke, still unconscious and unable
to resist. Feverishly they began to bind him in the strait-jacket which
they had taken from the ambulance. Then they carried him and flung him
roughly on the floor of the library.

Still screaming, Eva fled to the next room, again bolting the door and
piling furniture frantically to barricade it. Again the Automaton rained
blow after blow on the door. It splintered, and his powerful fist began
breaking and overturning the barricade which the unfortunate girl had
improvised.

Wildly she looked about. Only a closet now offered refuge. The door was
splintered through. She could see the terrible face of the monster.

In the library, Locke, recovering by this time, began flopping and
twisting, spurred by the muffled screams from above-stairs as he worked
with miraculous dexterity to release himself from the strait-jacket.



CHAPTER VI


Locke struggled with superhuman effort to release himself from the
strait-jacket in which he was held prisoner. The throat-straps pressed
against the neck muscles and the strain on the straps could be heard
like pistol-shots as the leather stretched under his prodigous efforts.

With every nerve keyed up and his reflexes answering his keen brain, he
swayed backward and forward, rolled from side to side until his
shoulder-blades were thrown completely out of joint. The pain was
intense, but he summoned every ounce of strength at his command and
finally succeeded in getting one of his arms free by gradually working
his body toward a settee, where, with his elbow on the seat, he pushed
his disjointed arm over his head.

Agony was written all over his face as at last with a final effort he