“Oh, some Indian conjuror,” said the doctor lightly; “a fraud, of course.”

“You don’t believe in magic?” asked Father Brown, without looking up.

“O crickey! magic!” said the doctor.

“It’s very beautiful,” said the priest in a low, dreaming voice; “the colours are very beautiful.  But it’s the wrong shape.”

“What for?” asked Flambeau, staring.

“For anything.  It’s the wrong shape in the abstract.  Don’t you ever feel that about Eastern art?  The colours are intoxicatingly lovely; but the shapes are mean and bad—­ deliberately mean and bad.  I have seen wicked things in a Turkey carpet.”

“Mon Dieu!” cried Flambeau, laughing.

“They are letters and symbols in a language I don’t know; but I know they stand for evil words,” went on the priest, his voice growing lower and lower.  “The lines go wrong on purpose—­like serpents doubling to escape.”

“What the devil are you talking about?” said the doctor with a loud laugh.

Flambeau spoke quietly to him in answer.  “The Father sometimes gets this mystic’s cloud on him,” he said; “but I give you fair warning that I have never known him to have it except when there was some evil quite near.”

“Oh, rats!” said the scientist.

“Why, look at it,” cried Father Brown, holding out the crooked knife at arm’s length, as if it were some glittering snake.  “Don’t you see it is the wrong shape?  Don’t you see that it has no hearty and plain purpose?  It does not point like a spear.  It does not sweep like a scythe.  It does not look like a weapon.  It looks like an instrument of torture.”

“Well, as you don’t seem to like it,” said the jolly Harris, “it had better be taken back to its owner.  Haven’t we come to the end of this confounded conservatory yet?  This house is the wrong shape, if you like.”

“You don’t understand,” said Father Brown, shaking his head.  “The shape of this house is quaint—­it is even laughable.  But there is nothing wrong about it.”

As they spoke they came round the curve of glass that ended the conservatory, an uninterrupted curve, for there was neither door nor window by which to enter at that end.  The glass, however, was clear, and the sun still bright, though beginning to set; and they could see not only the flamboyant blossoms inside, but the frail figure of the poet in a brown velvet coat lying languidly on the sofa, having, apparently, fallen half asleep over a book.  He was a pale, slight man, with loose, chestnut hair and a fringe of beard that was the paradox of his face, for the beard made him look less manly.  These traits were well known to all three of them; but even had it not been so, it may be doubted whether they would have looked at Quinton just then.  Their eyes were riveted on another object.

Exactly in their path, immediately outside the round end of the glass building, was standing a tall man, whose drapery fell to his feet in faultless white, and whose bare, brown skull, face, and neck gleamed in the setting sun like splendid bronze.  He was looking through the glass at the sleeper, and he was more motionless than a mountain.