'Perfectly unnecessary,' thought Roger, as he left him to it, 'because the inspector will ask exactly the same ones all over again as soon as he arrives; but they always do it.' He went upstairs once more.
Most of the party were collected now in the big room with the side open to the head of the well staircase, where the bar had been set up. Nearly everyone was extremely tired, and conversation was only spasmodic, but bed was out of the question. Ronald had already warned them that the police would almost certainly want to question each person. Standing about, or thrown into the big leather armchairs, they stared moodily into the still glowing fire.
At Roger's arrival a flicker of interest went round; and Dr. Chalmers asked whether Frank Mitchell had yet arrived.
"No," Roger explained, "but the police have. A constable. He says the inspector will be here in five or ten minutes."
He looked round the room. There was no scratch visible on any face. He had hardly expected that there would be. He joined Dr. Chalmers by the fireplace and opened a low - toned conversation. "Did you arrive at any conclusion as to how long she'd been dead?" he asked.
Dr. Chalmers looked at him inquiringly. "How long?" he repeated.
"Yes. I was just wondering whether she did it immediately after she rushed out of the ballroom or whether she brooded about it first."
"Oh, I see. Well, it's difficult to say to a few minutes, you know. I took the temperature of the body, and from that, and certain other indications, I should say that, allowing for the temperature of the outside air, she must have been dead at least two hours."
"Two hours," Roger said thoughtfully. "Then she probably did it at once."
"Oh, I think so, undoubtedly. She made the scene, my wife told me, just after I was called out."
"Yes," said Roger inattentively. "Yes. By the way, what's the local police inspector like?"
"A very good fellow. Not a fusser, but quite thorough. He'll go into all details, of course, but in such a straightforward case there's not very much he can do, is there?"
"No," said Roger. "I suppose there isn't."
His eyes were on the top of the staircase, perfectly visible through the low balustrade which had replaced the wall on that side of the room. The staircase ended in a small landing, off which the ballroom opened. The landing ran on for a few yards past the ballroom door, and at the end on the left there rose the short flight of stairs which led up onto the roof. This flight pierced through one of the remaining gables, so that its upper half was concealed from the barroom; but the lower half, and the whole of the landing, was perfectly visible. Anyone mounting to the roof would therefore be under the observation of anyone standing at the bar.
The conversation with Dr. Chalmers petered out as Roger pondered over his very meagre two and two and tried to make them into a robust four. Anyone going up onto the roof could be seen by anyone in the barroom. But nobody knew where Ena Stratton had gone; therefore nobody had been in the barroom just then, because the most absorbed toper could not have remained oblivious of her exit and passage. Therefore, if her murderer followed her almost at once onto the roof, again nobody was in the barroom, or in all probability nobody, to mark his passage either. But of course one must not forget that the murderer might have been on the roof already and met her there.
Anyhow, the obvious question was: who was in the ballroom just then and stayed there? It was possible at any rate to eliminate, if one could not construct.
Quite unconscious of the fact that to Dr. Chalmers his conduct might appear extremely rude, Roger pushed his hands in his pockets, turned his back on the other man, and wandered, absorbed in his thoughts, onto the landing, where he propped his back against the stalwart pillar which ended the balustrade, and frowned ferociously as he tried to throw his memory back over the last two hours.
First of all Dr. Chalmers himself was eliminated, as he had not been on the premises at all. Then Ronald, Mrs. Lefroy, Celia Stratton, and Mrs. Williamson had been with himself in the group which had tried to be kind to David Stratton. Yes, and Margot Stratton and Mike Armstrong. So they were all cleared. Whom did that leave? Williamson, Colin Nicolson, Mrs. Chalmers, Dr. and Mrs. Mitchell - but the last two had been the first to begin the dancing again (Roger distinctly remembered that), just before he himself had led David Stratton - why, dash it all, he himself had been at the bar within a few minutes of Mrs. Stratton's disappearance! He himself had been mounting guard over the only way of access to the roof. And had anyone passed along the landing and gone up there? Roger smiled to himself with exasperation. For the life of him he could not say. Of so much value is the evidence of the man on the spot. Roger Sheringham himself simply had not the faintest idea whether anyone had slipped out of the ballroom or not.
Nevertheless, this line of inquiry had not been quite fruitless. One thing at any rate was certain. David Stratton, who after all might be said to have a greater motive than anyone else, could not possibly have murdered his wife. During the really critical period he had been in Roger's own company. Well, that was one step, and a big one.
Roger looked up, to find Colin Nicolson talking to him. ". . . thought about?" said Colin.
"Do you mind saying that again, Colin?" said Roger politely.
"I said, 'Well, what's the great man plunged in thought about?' Not very well put perhaps, but that's what I said." Nicolson lifted a hand and felt, in the eternal gesture of the dinner - jacketed male, the sit of his tie.
Roger looked at the hand with interest. Just above the knuckles ran a long new scratch. It was impossible, of course, that Colin Nicolson could be the murderer of Mrs. Stratton. Absolutely and entirely out of the question. For one thing Colin would no more commit a murder than rob a blind widow, and for another he scarcely knew Mrs. Stratton at all - possibly had not spoken to her the whole evening. It was quite out of the question that Colin could have done such an incredible thing. Nevertheless Roger had been looking for someone who bore a nice new scratch somewhere visible, and here was a nice new scratch on Colin. Colin at any rate must account for the scratch.
"What was I thinking about?" Roger repeated vaguely. "Ah!"
"Very interesting, no doubt. Well, this is a nice business, I must say. How long do you think the police are going to keep us hanging about?"
"Oh, most of the night, I expect. You seem to have scratched your hand, Colin," Roger said mildly.
"Ach, yes. A nasty jab."
"Yes. Come up on the roof."
"On the roof?"
"I want a mouthful of fresh air."
"It'll be deuced parky fresh air. Besides, we've only just come down. No, no. If you want more fresh air, you can go up there alone."
"As a matter of fact, I want to speak to you rather particularly, Colin. Away from these people."
"Ach, you're a nuisance, Roger. All right, I suppose you'll give me no peace till I do."
Roger led an unwilling Colin out on the roof. "Ah, that's better. You ought to do something about that scratch, Colin. How did you get it?"
"Oh, it's nothing. Do you expect me to faint at every wee scratch I get? Well, what do you want to say, now you've got me here?" asked Colin turning up the collar of his coat. "For pity's sake hurry up and get it over."
Roger took the other's hand and examined the scratch. It was broad but not deep.
"How did you get it, Colin?" he repeated.
"Ach, man, what's it matter?"
"I'd just like to know."
Colin stared at him. "You're very suspicious. What's the idea?"