Must have been picked up by somebody and dropped in a post box.
"There, that's done," she said to herself, as the lid of the post box clicked upon her letters.
I appealed to him because he is aware that Mrs. Laing induced your groom to unlock the post–box and hand her my letter.
Then rings a bell—the hotel servants are now astir—and directs the letter to be dropped into the post box.
He said that he intended to take the letter on shore and slip it into a post box so that the censor should not see it.
Then a sure footed serving man was intrusted with the letter and told to seek a post box on the mountain side.