“Perhaps the old man changed his mind and destroyed it himself,” I suggested.

Poirot rose to his feet, dusting his knees with his usual care.

“That may be,” he admitted. “One of your more sensible observations, Hastings. Well, we can do no more here. We have done all that mortal man can do. We have successfully pitted our wits against the late Andrew Marsh’s; but, unfortunately, his niece is no better off for our success.”

By driving to the station at once, we were just able to catch a train to London, though not the principal express. Poirot was sad and dissatisfied. For my part, I was tired and dozed in a corner. Suddenly, as we were just moving out of Taunton, Poirot uttered a piercing squeal.

“ Vite , Hastings! Awake and jump! But jump I say!”