It all occupied only a few minutes, and then Andrews, slowly opening his rigidly crooked fingers, stood panting and looking down at the distorted face of the dead man.

For once in his life the Scotsman was sober, and turning to Dr. Kreener: 

“I have waited seven long years for this,” he said, “and I’ll hang wi’ contentment.”

I can never forget the ensuing moments, in which, amid a horrible silence broken only by the ticking of a clock and the heavy breathing of Colquhoun (so long known to us as Andrews) we stood watching the contorted body on the settee.

And as we watched, slowly the rigid limbs began to relax, and Tcheriapin slid gently on to the floor, collapsing there with a soft thud, where he squatted like some hideous Buddha, resting back against the cushions, one spectral yellow hand upraised, the fingers still clutching a big gold tassel.

Andrews (for so I always think of him) was seized with a violent fit of trembling, and he dropped into the chair, muttering to himself and looking down wild-eyed at his twitching fingers.  Then he began to laugh, high-pitched laughter, in little short peals.

“Here!” cried the doctor sharply.  “Drop that!”

Crossing to Andrews, he grasped him by the shoulders and shook him roughly.

The laughter ceased, and: 

“Send for the police,” said Andrews in a queer, shaky voice.  “Dinna fear but I’m ready.  I’m only sorry it happened here.”

“You ought to be glad,” said Dr. Kreener.

There was a covert meaning in the words—­a fact which penetrated even to the dulled intelligence of the Scotsman, for he glanced up haggardly at his friend.

“You ought to be glad,” repeated Dr. Kreener.

Turning, he walked to the laboratory door and locked it.  He next lowered all the blinds.

“I pray that we have not been observed,” he said, “but we must chance it.”

He mixed a drink for Andrews and himself.  His quiet, decisive manner had had its effect, and Andrews was now more composed.  Indeed, he seemed to be in a half-dazed condition; but he persistently kept his back turned to the crouching figure propped up against the settee.

“If you think you can follow me,” said Dr. Kreener abruptly, “I will show you the result of a recent experiment.”

Unlocking a cupboard, he took out a tiny figure some two inches long by one inch high, mounted upon a polished wooden pedestal.  It was that of a guinea-pig.  The flaky fur gleamed like the finest silk, and one felt that the coat of the minute creature would be as floss to the touch; whereas in reality it possessed the rigidity of steel.  Literally one could have done it little damage with a hammer.  Its weight was extraordinary.