“Let us go in to him,” said Father Brown shortly.  “You can leave Mr. Atkinson alone.  I have had him in sight since we heard Quinton’s voice.”

“I will stop here and watch him,” said Flambeau hurriedly.  “You go in and see.”

The doctor and the priest flew to the study door, unlocked it, and fell into the room.  In doing so they nearly fell over the large mahogany table in the centre at which the poet usually wrote; for the place was lit only by a small fire kept for the invalid.  In the middle of this table lay a single sheet of paper, evidently left there on purpose.  The doctor snatched it up, glanced at it, handed it to Father Brown, and crying, “Good God, look at that!” plunged toward the glass room beyond, where the terrible tropic flowers still seemed to keep a crimson memory of the sunset.

Father Brown read the words three times before he put down the paper.  The words were:  “I die by my own hand; yet I die murdered!” They were in the quite inimitable, not to say illegible, handwriting of Leonard Quinton.

Then Father Brown, still keeping the paper in his hand, strode towards the conservatory, only to meet his medical friend coming back with a face of assurance and collapse.  “He’s done it,” said Harris.

They went together through the gorgeous unnatural beauty of cactus and azalea and found Leonard Quinton, poet and romancer, with his head hanging downward off his ottoman and his red curls sweeping the ground.  Into his left side was thrust the queer dagger that they had picked up in the garden, and his limp hand still rested on the hilt.

Outside the storm had come at one stride, like the night in Coleridge, and garden and glass roof were darkened with driving rain.  Father Brown seemed to be studying the paper more than the corpse; he held it close to his eyes; and seemed trying to read it in the twilight.  Then he held it up against the faint light, and, as he did so, lightning stared at them for an instant so white that the paper looked black against it.

Darkness full of thunder followed, and after the thunder Father Brown’s voice said out of the dark:  “Doctor, this paper is the wrong shape.”

“What do you mean?” asked Doctor Harris, with a frowning stare.

“It isn’t square,” answered Brown.  “It has a sort of edge snipped off at the corner.  What does it mean?”

“How the deuce should I know?” growled the doctor.  “Shall we move this poor chap, do you think?  He’s quite dead.”

“No,” answered the priest; “we must leave him as he lies and send for the police.”  But he was still scrutinising the paper.

As they went back through the study he stopped by the table and picked up a small pair of nail scissors.  “Ah,” he said, with a sort of relief, “this is what he did it with.  But yet—­” And he knitted his brows.

“Oh, stop fooling with that scrap of paper,” said the doctor emphatically.  “It was a fad of his.  He had hundreds of them.  He cut all his paper like that,” as he pointed to a stack of sermon paper still unused on another and smaller table.  Father Brown went up to it and held up a sheet.  It was the same irregular shape.