"How do you mean?" asked the detective quickly.
Father Brown turned his moon face up to the narrow façade of the house and blinked hopelessly up. Following his eyes, they saw that right at the top of this otherwise blind back quarter of the building, an attic window stood open.
"Don't you see," he explained, pointing a little awkwardly like a child, "he was thrown down from there?"
Gilder frowningly scrutinised the window, and then said: "Well, it is certainly possible. But I don't see why you are so sure about it."
Brown opened his grey eyes wide. "Why," he said, "there's a bit of rope round the dead man's leg. Don't you see that other bit of rope up there caught at the corner of the window?"
At that height the thing looked like the faintest particle of dust or hair, but the shrewd old investigator was satisfied. "You're quite right, sir," he said to Father Brown; "that is certainly one to you."
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.
"Be careful what you say," said Royce gruffly, "you'll frighten Miss Armstrong."
"I hope so," said the man with the clear voice.
As the woman winced and everyone else wondered, he went on: "I am somewhat used to Miss Armstrong's tremors. I have seen her trembling off and on for years. And some said she was shaking with cold and some she was shaking with fear, but I know she was shaking with hate and wicked anger—fiends that have had their feast this morning. She would have been away by now with her lover and all the money but for me. Ever since my poor old master prevented her from marrying that tipsy blackguard——"
"Stop," said Gilder very sternly. "We have nothing to do with your family fancies or suspicions. Unless you have some practical evidence, your mere opinions——"
"Oh! I'll give you practical evidence," cut in Magnus, in his hacking accent. "You'll have to subpoena me, Mr. Inspector, and I shall have to tell the truth. And the truth is this: An instant after the old man was pitched bleeding out of the window, I ran into the attic, and found his daughter swooning on the floor with a red dagger still in her hand. Allow me to hand that also to the proper authorities." He took from his tail-pocket a long horn-hilted knife with a red smear on it, and handed it politely to the sergeant. Then he stood back again, and his slits of eyes almost faded from his face in one fat Chinese sneer.
Merton felt an almost bodily sickness at the sight of him; and he muttered to Gilder: "Surely you would take Miss Armstrong's word against his?"
Father Brown suddenly lifted a face so absurdly fresh that it looked somehow as if he had just washed it. "Yes," he said, radiating innocence, "but is Miss Armstrong's word against his?"
The girl uttered a startled, singular little cry; everyone looked at her. Her figure was rigid as if paralysed; only her face within its frame of faint brown hair was alive with an appalling surprise. She stood like one of a sudden lassooed and throttled.
"This man," said Mr. Gilder gravely, "actually says that you were found grasping a knife, insensible, after the murder."
"He says the truth," answered Alice.
The next fact of which they were conscious was that Patrick Royce strode with his great stooping head into their ring and uttered the singular words: "Well, if I've got to go, I'll have a bit of pleasure first."
His huge shoulder heaved and he sent an iron fist smash into Magnus's bland Mongolian visage, laying him on the lawn as flat as a starfish. Two or three of the police instantly put their hands on Royce; but to the rest it seemed as if all reason had broken up and the universe were turning into a brainless harlequinade.
"None of that, Mr. Royce," Gilder had called out authoritatively. "I shall arrest you for assault."
"No, you won't," answered the secretary in a voice like an iron gong, "you will arrest me for murder."
Gilder threw an alarmed glance at the man knocked down; but since that outraged person was already sitting up and wiping a little blood off a substantially uninjured face, he only said shortly: "What do you mean?"
"It is quite true, as this fellow says," explained Royce, "that Miss Armstrong fainted with a knife in her hand. But she had not snatched the knife to attack her father, but to defend him."
"To defend him," repeated Gilder gravely. "Against whom?"
"Against me," answered the secretary.
Alice looked at him with a complex and baffling face; then she said in a low voice: "After it all, I am still glad you are brave."
"Come upstairs," said Patrick Royce heavily, "and I will show you the whole cursed thing."
The attic, which was the secretary's private place (and rather a small cell for so large a hermit), had indeed all the vestiges of a violent drama. Near the centre of the