"Very much indeed. Now, you are an exceedingly clever man, Marquis, and you may be able to help me. It happens that I am deeply interested in the Grand Coast Express murder; in fact, I have devoted the last two months to its solution."
"With no success whatever, my dear Colonel?" the Marquis murmured.
"On the contrary, my dear Marquis, with absolute satisfaction. I am quite sure that you will be interested in my story."
The Marquis raised his cigarette graciously.
"You are very good to give me your confidence," he said. "Pray proceed."
"Thank you. I will not bore you with any preliminary details, for they are too recent to have faded from your memory. Sufficient that we have a murder committed in an express train; we have the disappearance of eight thousand pounds in gold, without any trace of the criminal. That he was on the train at the start is obvious. That he was not in any of the carriages conveying ordinary passengers is equally obvious. It is also certain that he left the train after the commission of the crime. Doubtless you read the evidence of the guard to prove that nobody left the train after the viaduct leading to Lydmouth station was reached. Therefore, the murderer contrived to make his escape when the express was traveling at sixty miles per hour."
"Is not all this superfluous?" the Marquis asked.
"Well, not quite. I am going to tell you how the murderer joined the train and how he left it after the murder and the robbery."
"You are going to tell me that! Is it possible?"
"I think so," Merrick said modestly. "Now, Mr. Skidmore had a compartment to himself. He was locked in the very last thing, and nobody joined the train afterward. Naturally a—well—an amateur detective like myself wanted to know who was in the adjoining compartments. Three of these could be dismissed at once. But in the fourth there was a corpse——"