"I mean, did you hear a shot being fired at him?"
The sentry shook his head.
"The man's been murdered by a pistol shot, right enough," declared Terence. "Either the noise of the train deadened the report, or else the murderer muffled the weapon in a cloth. The best thing you can do, guard, is to take the poor fellow's body on to the next station."
"An my relief ain't due for another hour and a quarter!" gasped the remaining sentry. He had been completely unnerved at the sight of his chum being foully done to death.
"All right, my man," said Terence, "I'll stop with you. I suppose I can get to Edinburgh by another train, guard?"
"Yes, sir," replied that official. "Next station's only a matter of three or four miles. But you won't be lonely. There's half a dozen troop trains on the up-line within the next three hours. I'll take the corpse, sir, if these gents'll bear a hand. 'Tain't the first poor chap that's been done in like this: not by a long way. Good-night, sir, and good luck."
Presently the mail train resumed its journey. The sentry, nervously fingering his rifle, seemed grateful to the young officer, but at the same time he regarded him with a certain amount of suspicion. Perhaps his naval uniform was a disguise. He might be an accomplice of the man who had murdered his chum. Troop trains? That started a fresh chain of surmises. This dastardly act might be that of a spy, intent upon damaging the tunnel and wrecking the crowded trains.
"Look here, my man," said the lieutenant, "are you game to going and standing where your chum was posted?"
"What for, sir?" asked the soldier, with obvious reluctance at the suggestion.
"Oh, never mind. I'll go. You remain here. If you see or hear anything suspicious, don't hesitate—shoot. You're a fairly good shot, I hope?"