The Sergeant puffed disappointedly on his cigar.
"So he went up the balcony steps, entered the French doors, crossed Ada's room to the hall, did his dirty work, and then—disappeared! A sweet case this is!" He clicked his tongue with disgust.
"The man may have gone out by the front door," suggested Markham.
The Sergeant made a wry face and bellowed for Sproot, who entered immediately.
"Say, which way did you go up-stairs when you heard the shot?"
"I went up the servants' stairs, sir."
"Then some one mighta gone down the front stairs at the same time without your seeing him?"
"Yes, sir; it's quite possible."
"That's all."
Sproot bowed and again took up his post at the front door.
"Well, it looks like that's what happened, sir," Heath commented to Markham. "Only how did he get in and out of the grounds without being seen? That's what I want to know."
Vance was standing by the window gazing out upon the river.
"There's something dashed unconvincing about those recurrent spoors in the snow. Our eccentric culprit is altogether too careless with his feet and too careful with his hands. He doesn't leave a finger-print or any other sign of his presence except those foot-tracks—all nice and tidy and staring us in the face. But they don't square with the rest of this fantastic business."
Heath stared hopelessly at the floor. He was pat-
