Deftly they strapped him to the chair; his wrists and elbows were securely fastened to the arms, and his ankles to the legs of the ma.s.sive piece of furniture.

From where he sat Poltavo confronted Farrington, but the big man's mask-like face did not move, nor his eyes waver as he surveyed his treacherous prisoner. Then Fall knelt down and did something, and Poltavo heard the ripping and tearing of cloth.

They were slitting up each trouser leg, and he could not understand why.

"Is this a joke?" he asked with a desperate attempt at airiness.

No reply was made. Poltavo watched his captors curiously. What was the object of it all? The two men busy at the chair lifted a number of curious-looking objects from the floor; they clamped one on each wrist, and he felt the cold surface of some instrument pressing against each calf. Still he did not realize the danger, or the grim determination of these men whose secret he would have betrayed.

"Mr. Farrington," he appealed to the big man, "let us have an understanding. I have played my game and lost."

"You have indeed," said Farrington.

They were the first words he had spoken.

"Give me enough to get out of the country," Poltavo appealed, "just the money that I have in my pocket, and I promise you that I will never trouble you again."

"My friend," said Farrington, "I have trusted you too long. You forced yourself upon me when I did not desire you, you thwarted me at every turn, you betrayed me whenever it was possible to betray me, or whenever it was to your advantage to do so, and I am determined that you shall have no other chance of doing me an injury."

"What is this foolery?" asked Poltavo, in a mixture of blind fear and rage. They had unlocked the handcuffs and taken them off him, and now for the first time Poltavo noticed that the curious bronze clamps on his wrists were attached by thick green cords to a plug in the wall.

He shrieked aloud as he saw this, and the full horror of the situation flashed upon him.

"My G.o.d," he screamed, "you are not going to kill me?"

Farrington nodded slowly.

"We are going to kill you painlessly, Poltavo," he said. "It was your life or ours. We do not desire to cause you unnecessary suffering, but here is the end of the adventure for you, my friend."

"You are not going to electrocute me?" croaked the man in the chair, in a hoa.r.s.e cracked voice. "Don't say that you are going to electrocute me, Farrington! It is diabolical, it is terrible. Give me a chance of life!

Give me a pistol, give me a knife, but fight me fair. Treat me as you will; hand me to the police, anything but this; for G.o.d's sake, Farrington, don't do this!"

The doctor reached down and lifted a leather helmet from the floor and placed it gently over the doomed man's head.

"Don't do it, Farrington." Poltavo's m.u.f.fled voice came painfully from behind the leather screen. "Don't! I swear I will not betray you."

Farrington made a little signal and the doctor walked to the wall and placed his hand upon a black switch.

"I will not betray you," said the man in the chair in hollow tones.

"Give me a chance. I will not tell them anything that you----"

He did not speak again, for the black switch had been pressed down and death came with merciful swiftness.

They stood watching the figure. A slight quivering of the hands and then Farrington nodded and the doctor turned the switch over again.

Rapidly they unfastened the straps, and the limp thing which was once human, with a brain to think and a capacity for life and love, slipped out of the chair in an inanimate heap upon the ground.

So pa.s.sed Ernesto Poltavo, an adventurer and a villain, in the prime of his life.

Farrington looked down upon the body with sombre eyes and shrugged his shoulders.

He had opened his mouth to speak and Fall had walked to the switchboard and was about to put the deadly apparatus out of gear, when a sharp voice made them both turn.

"Hands up!" it said.

The stone door, through which Poltavo had pa.s.sed to his doom from the corridor without, was wide open, and in the doorway stood T. B. and a little behind him Ela, and in T. B.'s hand was a pistol.

CHAPTER XX

T. B. Smith's inspection of the Secret House had yielded nothing satisfactory; he had not expected that it would; he was perfectly satisfied that the keen, shrewd brains which dominated the menage would remove any trace there was of foul play.

"Where now?" asked Ela, as they turned out of the house.

"Back to Moor Cottage," said T. B., climbing into the car. "I am certain that we are on the verge of our big discovery. There is a way out of the cottage by some underground chamber, a way by which first Lady Constance and then Poltavo were smuggled, and if it is necessary I am going to smash every panel in those two ground floor rooms, but I will find the way in to Mr. Farrington's mystery house."

For half an hour the two men were engaged in the room from which Poltavo had been taken. They probed with centre bits and gimlets into every portion of the room.

The first discovery that they made was that the oaken panels of the chamber were backed with sheet iron or steel.

"It is a hopeless job; we shall have to get another kind of smith here to tear down all the panellings," said T. B., lighting the gloom of his despair with a little flash of humour.

He fingered the tiny locket absently and opened it again.

"It is absurd," he laughed helplessly. "Here is the solution in these simple words, and yet we brainy folk from the Yard cannot understand them!"

"G.o.d sav the Keng!" said Ela ruefully. "I wonder how on earth that is going to help us."

A gasp from T. B. made him turn his face to his chief.

T. B. Smith was pointing at the piano. In two strides he was across the room, and sitting on the stool he lifted the cover and struck a chord.

The instrument sounded a little flat and apparently had not received the attention of a tuner for some time.

"I am going to play 'G.o.d save the King,'" said T. B. with a light in his eyes, "and I think something is going to happen."

Slowly he pounded forth the familiar tune; from beginning to end he played it, and when he had finished he looked at Ela.

"Try it in another key," suggested Ela, and again T. B. played the anthem. He was nearing the last few bars when there was a click and he leapt up. One long panel had disappeared from the side of the wall. For a moment the two men looked at one another. They were alone in the house, although a policeman was within call. The main force was gathered in the vicinity of the Secret House.

T. B. flashed the light of his indispensable and inseparable little electric lamp into the dark interior.

"I will go in first and see what happens," he said.

"I think we will both go together," said Ela grimly.