For Poirot, uttering a hoarse and inarticulate cry, again annihilated his masterpiece of cards and putting his hands over his eyes swayed backwards and forwards, apparently suffering the keenest agony.
Good heavens Poirot! I cried. What is the matter? Are you taken ill?
No, no, he gasped. It is—it is—that I have an idea!
The Mysterious Affair at Styles (1920)