The ticking seemed to come not only from this particular section of wall, but lead on through different cars of the Train.
Indeed, it grew stronger as I advanced.

Along the way, I passed through what seemed to be the car of Probable Impossibilities, then Old Proverbs, then the Tiny Car of Jumbo Oxymorons. The list grew even stranger as I went, ever searching for that ticking that grew louder and louder. In fact, it sounded as though there were more than one source to the noises.

Finally, I passed through a worn door to the last car. It was dimly lit, but flooded with the sounds of thousands of clocks. A man sat in a chair, observing some and taking notes.

“Hello?”

He spun around. “Hello. I didn’t notice you here, are you lost?”

“No, I came out of curiosity.”

“You must’ve passed through the Car of Enigmatic Curiosities, however.”

“I suppose. What is this room?”

“Usually our passengers don’t come back here. You see, every clock in here shows how long each person here will live.”