look for a rather tall man, cool-headed, familiar with fire-arms, a good shot, and fairly well known to the deceased—a man who was aware that Benson was going to dinner with Miss St. Clair, or who had reason to suspect the fact."
Markham looked narrowly at Vance for several moments.
"I think I understand. . . . Not a bad theory, either. You know, I'm going to suggest immediately to Heath that he investigate more thoroughly Captain Leacock's activities on the night of the murder."
"Oh, by all means," said Vance carelessly, going to the piano.
Markham watched him with an expression of puzzled interrogation. He was about to speak when Vance began playing a rollicking French café song which opens, I believe, with
"Ils sont dans les vignes les moineaux."
