"This is the way of it, Strawn.... Nita and Sprague rowed last night. Sprague tried to make it up, but Nita must have been through with him. Probably told him last night to clear his things out and not come back. She thought he had done so; probably he did leave before she got up. At any rate she was so sure he was gone and his things with him that she and Lydia went to town this morning and left Ralph Hammond here to go through the place as freely as he liked, making his estimates on the job of finishing up the other half of this floor. And Ralph—but let that wait for the moment."
"Got any real proof that it was Sprague who stayed here and not the Hammond boy?" Strawn interrupted shrewdly.
"I'm coming to the proof," Dundee assured him, "or rather, the rest of the proof that I haven't already given you. You're damned hard to convince, chief! But let me go on with my theory, which I think covers the facts.... At luncheon, when Nita received that note from Sprague, I imagine she got a hunch that he hadn't taken her seriously, that he had not removed his belongings. You remember Penny Crain said Nita had Lydia follow her into her bedroom, as soon as Nita got home from the luncheon?... Well, it's my hunch that Nita asked Lydia if Sprague's things were gone when she cleaned these rooms this morning, and that Lydia said no. Nita then probably told Lydia to pack them herself, and I feel positive that Lydia did so, for she must have felt safe when she protested to me that Sprague was not Nita's lover. I also feel sure that Sprague arrived at least half an hour before he said he did, by some back path across the meadow; that he came up to these rooms that he considered his, found his things packed, but went about shaving and changing his shirt and collar, regardless. I also feel sure that Lydia followed him upstairs to explain and impress upon him that Nita had meant what she said. And it is quite likely that she was not through picking up after him when he descended by the back stairs and surprised Janet Raymond on the front porch. That accounts, of course, for Lydia's not hearing the kitchen bell the first time Mrs. Dunlap rang."
"Umm," Strawn grunted. "What about the proofs you're holding back?"
"Come along, chief—you, too, Carraway!" Dundee answered, and led the way into the bathroom. "I felt sure these rooms would yield a very definite clue, even though Sprague, when he sneaked back tonight to get his tell-tale bag, apparently made every effort to wipe his fingerprints off the furniture and bathroom fixtures.... Now, Carraway, if you'll step upon this little stool and look along the top of this medicine cabinet, you'll find what I found—and didn't touch."
The fingerprint expert did as he was told. When he stepped down he was holding, between the very tips of his fingers, a safety razor blade.
"No dust on it, you see," Dundee pointed out. "Now if you don't find Dexter Sprague's fingerprints on it, my whole theory topples."
"How am I going to know whose fingerprints they are till we get hold of Sprague?" Carraway asked reasonably.
"We don't need him—for that purpose, at least," Dundee assured him. "Downstairs in the living room, on a little table in the southeast corner of the room, you'll find a red glass ashtray which no one but Dexter Sprague used all evening. It was clean and empty when I saw him use it first. I think you'll find on it all the prints you need."
"So you think Sprague killed her because she was through with him?" Strawn asked.