"No doubt he is right," said Thorndyke. "But now, tell me, do you think it is possible for any person to board or leave the train on the off-side unobserved? Could a man, for instance, enter a compartment on the off-side at one station and drop off as the train was slowing down at the next, without being seen?"
"I doubt it," replied the station-master. "Still, I wouldn't say it is impossible."
"Thank you. Oh, and there's another question. You have a gang of men at work on the line, I see. Now, do those men belong to the district?"
"No, sir; they are strangers, every one, and pretty rough diamonds some of 'em are. But I shouldn't say there was any real harm in 'em. If you was suspecting any of 'em of being mixed up in this—"
"I am not," interrupted Thorndyke rather shortly. "I suspect nobody; but I wish to get all the facts of the case at the outset."
"Naturally, sir," replied the abashed official; and we pursued our way in silence.
"Do you remember, by the way," said Thorndyke, as we approached the empty coach, "whether the off-side door of the compartment was closed and locked when the body was discovered?"
"It was closed, sir, but not locked. Why, sir, did you think—?"
"Nothing, nothing. The sealed compartment is the one, of course?"
Without waiting for a reply, he commenced his survey of the coach, while I gently restrained our two companions from shadowing him, as they were disposed to do. The off-side footboard occupied his attention specially, and when he had scrutinized minutely the part opposite the fatal compartment, he walked slowly from end to end with his eyes but a few inches from its surface, as though he was searching for something.