THE INNOCENCE OF FATHER BROWN
brows. "It's not easy to hack a neck through even clumsily, and this was a very clean cut. It could be done with a battle-axe or an old headsman's axe, or an old two-handed sword."
"But, good heavens!" cried the Duchess, almost in hysterics, "there aren't any two-handed swords and battle-axes round here."
Valentin was still busy with the paper in front of him. "Tell me," he said, still writing rapidly, "could it have been done with a long French cavalry sabre?"
A low knocking came at the door, which, for some unreasonable reason, curdled everyone's blood like the knocking in Macbeth. Amid that frozen silence Dr. Simon managed to say: "A sabre—yes, I suppose it could."
"Thank you," said Valentin. "Come in, Ivan."
The confidential Ivan opened the door and ushered in Commandant Neil O'Brien, whom he had found at last pacing the garden again.
The Irish officer stood up disordered and defiant on the threshold. "What do you want with me?" he cried.
"Please sit down," said Valentin in pleasant, level tones. "Why, you aren't wearing your sword. Where is it?"
"I left it on the library table," said O'Brien, his brogue deepening in his disturbed mood. "It was a nuisance, it was getting"
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