I was only too happy to have the privilege of going with him. It was most interesting to watch the workings of so inscrutable a mind. As we drove under the lofty iron roof of the terminus I noticed a look of annoyance pass over his face.

“We are fifteen seconds ahead of our time,” he remarked, looking at the big clock. “I dislike having a miscalculation of that sort occur.”

The great Scotch Express stood ready for its long journey. The detective tapped one of the guards on the shoulder.

“You have heard of the so-called Pegram mystery, I presume?”

“Certainly, sir. It happened on this very train, sir.”

“Really? Is the same carriage still on the train?”

“Well, yes, sir, it is,” replied the guard, lowering his voice, “but of course, sir, we have to keep very quiet about it. People wouldn’t travel in it, else, sir.”

“Doubtless. Do you happen to know if anybody occupies the compartment in which the body was found?”

“A lady and gentleman, sir; I put ‘em in myself, sir.”

“Would you further oblige me,” said the detective, deftly slipping half-a-sovereign into the hand of the guard, “by going to the window and informing them in an offhand casual sort of way that the tragedy took place in that compartment?”