I changed the subject and was prattling on about our plans when the train entered a tunnel. “Edith,” came his voice, very calm indeed, “what is this?” My eyes had not yet adjusted to the abrupt dimness. “I don’t know—what does it feel like? Have you found the mustard pot?” “The light.” “Oh! It’s a tunnel. We’ll be through it shortly.” I made note of the fact that when Simon was alarmed, he sounded particularly calm.

