"Came by the noon post, sir.

The housekeeper signed for it." Brereton took the letter into the smoking-room and looked at it with a sudden surmise that it might have something to do with the matter which was uppermost in his thoughts.

He had had no expectation of any registered letter, no idea of anything that could cause any correspondent of his to send him any communication by registered post.
There was no possibility of recognizing the handwriting of the sender, for there was no handwriting to recognize: the address was typewritten.
And the postmark was London.
Brereton carefully cut open the flap of the envelope and drew out the enclosure--a square sheet of typewriting paper folded about a thin wad of Bank of England notes.

He detached these at once and glanced quickly at them.

There were six of them: all new and crisp--and each was for a hundred and fifty pounds.
Brereton laid this money aside and opened the letter.