The ball that evening was an acknowledged success, but, though he was an excellent dancer, and had his choice of the prettiest women in the room, Carne was evidently ill at ease. The number of times he stealthily examined his watch said this as plainly as any words. As a matter of fact, the last guest had scarcely arrived before he left the ball-room, and passed down the lobby towards the back stair-case, stopping en route to glance at the billiard-room door.
As he expected, it was closed, and a stalwart provincial policeman stood on guard before it.
He made a jocular reference about the treasure the constable was guarding, and, with a laugh at himself for forgetting the way to his bedroom, retraced his steps to the stairs, up which he passed to his own apartment. Belton was awaiting him there.
"It is ten minutes to ten, Belton," he said abruptly. "It must be now or never. Go down to the kitchen, and hang about there until the tray upon which the suppers of the guard are placed is prepared. When the footman starts with it for the Billiard-room, accompany him, and as he opens the green baize door leading into the house, manage by hook or crook, to hold him in conversation. Say something, and interrupt yourself by a severe fit of coughing. That will give me my cue. If anything should happen to me as I come downstairs, be sure that the man puts his tray down on the slab at the foot of the stairs and renders me assistance. I will manage the rest. Now be off."
Belton bowed respectfully and left the room. As he did so, Carne crossed to the dressing-table, and unlocked a small case standing upon it. From this he took a tiny silver-stoppered scent bottle, containing, perhaps, half an ounce of white powder. This he slipped into his waistcoat pocket, and then made for the door.
On the top of the back staircase he paused for a few moments to listen. He heard the spring of the green baize door in the passage below creak as it was pushed open. Next moment he distinguished Belton's voice. "It's true as I'm standing here," he was saying. "As I went up the stairs with the governor's hot water there she was coming along the passage. I stood back to let her pass, and as I did she----" (Here the narrative was interrupted by a violent fit of coughing.) On hearing this Carne descended the stairs, and, when he had got half-way down, saw the footman and his valet coming along the passage below. At the same instant he must have caught his foot in the stair carpet, for he tripped and fell headlong to the bottom.
"Heavens live!" cried Belton. "I do believe that's my governor, and he's killed." At the same time he ran forward to the injured man's assistance.
Carne lay at the foot of the stairs just as he had fallen, his head thrown back, his eyes shut, and his body curled up and motionless. Belton turned to the footman, who still stood holding the tray where he had stopped on seeing the accident, and said: "Put down those things and go and find Mr. Greenthorpe as quickly as you can. Tell him Mr. Carne has fallen downstairs, and I'm afraid is seriously injured."
The footman immediately disappeared. His back was scarcely turned, however, before Carne was on his feet.
"Excellent, my dear Belton," he whispered; and, as he spoke, he slipped his fingers into his waistcoat pocket. "Hand me up that tray, but be quiet, or the policeman round the corner will hear you."