“It was a hot, airless morning towards the end of June.
Poirot had a particular routine when opening his morning correspondence.
He picked up each letter, scrutinized it carefully and neatly slit the envelope
open with his papercutter“.
Dumb witness, Agatha Christie
“Eh bien, mon ami,” said Poirot, lighting one of his tiny cigarettes, ” we must map out a plan of campaign. Already I have made rough survey of the house, but I am of opinion that any clue will be found in this room. We shall have to g othrough the documents in the desk with meticulous care.(…)”