"To all stations. Stop Ambulance Motor No. LKO 9943. Arrest and detain driver and any person found therein. Warn all garages and report.--COMMISSIONER."

This order flashed from station to station throughout the night, and before the dawn, nine thousand policemen were on the look-out for the motor ambulance.

"There's a chance, of course," said Stafford, "but it is a poor chance."

He was looking white and heavy-eyed.

"I don't know, sir," said Southwick, his subordinate. "There's always a chance that a crook will do the obviously wrong thing. I suppose you've no theory as to where they have gone?"

"Not out of town--of that I'm certain," said King, "that is why the quest is so hopeless. Why, they'll have got to their destination hours before the message went out!"

They were standing in the girl's bedroom, which still reeked with chloroform, and all the clues were piled together on the table. There were not many. There was a pad of cotton-wool, a half-empty bottle of chloroform, bearing the label of a well-known wholesaler, and one of a pair of old wash-leather gloves, which had evidently been worn by somebody in his desire to avoid leaving finger-prints.

"We've not much to go on there," said Stafford disconsolately; "the chloroform may have been sold years ago. Any chemist would have supplied the cotton-wool, and as for the glove"--he picked it up and looked at it carefully, then he carried it to the light.

Old as it was, it was of good shape and quality, and when new had probably been supplied to order by a first-class glove-maker.

"There's nothing here," said Stafford again, and threw the glove back on the table.

A policeman came into the room and saluted.

"I've cycled over from the Yard, sir. We have had a message asking you to go at once to Sir Stanley Belcom's private house."

"How did Sir Stanley know about this affair?" asked Stafford listlessly.

"He telephoned through, sir, about five o'clock this morning. He often makes an early inquiry."

Stafford looked round. There was nothing more that he could do. He passed down the stairs into the street and jumped on to the motor-cycle which had brought him to the scene.

Sir Stanley Belcom lived in Cavendish Place, and Stafford had been a frequent visitor to the house. Sir Stanley was a childless widower, who was wont to complain that he kept up his huge establishment in order to justify the employment of his huge staff of servants. Stafford suspected him of being something of a sybarite. His dinners were famous, his cellar was one of the best in London and because of his acquaintances and friendships in the artistic sets, he was something of a dabbler in the arts he patronised.

The door was opened and an uncomfortable-looking butler was waiting on the step to receive Stafford.

"You'll find Sir Stanley in the library, sir," he said.

Despite his sorrow, Stafford could not help smiling at this attempt on the part of an English servant to offer the conventional greeting in spite of the hour.

"I'm afraid we've got you up early, Perkins," he said.

"Not at all, sir."

The man's stout face creased in a smile.

"Sir Stanley's a rare gentleman for getting up in the middle of the night and ordering a meal."

Stafford found his grey-haired chief, arrayed in a flowered silk dressing-gown, balancing bread on an electric toaster.

"Bad news, eh, Stafford?" he said. "Sit down and have some coffee. The girl is gone?"

Stafford nodded.

"And our unfortunate............