Almost as he spoke a special train with one carriage took the curve of the line on their left, and, stopping, disgorged another group of policemen, in whose midst was the hangdog visage of Magnus, the absconded servant.

“By Jove! they’ve got him,” cried Gilder, and stepped forward with quite a new alertness.

“Have you got the money!” he cried to the first policeman.

The man looked him in the face with a rather curious expression and said:  “No.”  Then he added:  “At least, not here.”

“Which is the inspector, please?” asked the man called Magnus.

When he spoke everyone instantly understood how this voice had stopped a train.  He was a dull-looking man with flat black hair, a colourless face, and a faint suggestion of the East in the level slits in his eyes and mouth.  His blood and name, indeed, had remained dubious, ever since Sir Aaron had “rescued” him from a waitership in a London restaurant, and (as some said) from more infamous things.  But his voice was as vivid as his face was dead.  Whether through exactitude in a foreign language, or in deference to his master (who had been somewhat deaf), Magnus’s tones had a peculiarly ringing and piercing quality, and the whole group quite jumped when he spoke.

“I always knew this would happen,” he said aloud with brazen blandness.  “My poor old master made game of me for wearing black; but I always said I should be ready for his funeral.”

And he made a momentary movement with his two dark-gloved hands.

“Sergeant,” said Inspector Gilder, eyeing the black hands with wrath, “aren’t you putting the bracelets on this fellow; he looks pretty dangerous.”

“Well, sir,” said the sergeant, with the same odd look of wonder, “I don’t know that we can.”

“What do you mean?” asked the other sharply.  “Haven’t you arrested him?”

A faint scorn widened the slit-like mouth, and the whistle of an approaching train seemed oddly to echo the mockery.

“We arrested him,” replied the sergeant gravely, “just as he was coming out of the police station at Highgate, where he had deposited all his master’s money in the care of Inspector Robinson.”

Gilder looked at the man-servant in utter amazement.  “Why on earth did you do that?” he asked of Magnus.

“To keep it safe from the criminal, of course,” replied that person placidly.

“Surely,” said Gilder, “Sir Aaron’s money might have been safely left with Sir Aaron’s family.”

The tail of his sentence was drowned in the roar of the train as it went rocking and clanking; but through all the hell of noises to which that unhappy house was periodically subject, they could hear the syllables of Magnus’s answer, in all their bell-like distinctness:  “I have no reason to feel confidence in Sir Aaron’s family.”

All the motionless men had the ghostly sensation of the presence of some new person; and Merton was scarcely surprised when he looked up and saw the pale face of Armstrong’s daughter over Father Brown’s shoulder.  She was still young and beautiful in a silvery style, but her hair was of so dusty and hueless a brown that in some shadows it seemed to have turned totally grey.