An interesting character, the signalman is a combination of diligence and superstition. While he calls to the narrator, the narrator believes him first to be "a spirit." The signalman returns the dubious look of the narrator, wondering if he has seen the narrator before, and marveling at what he has heard. Later, after they become friendly, the signalman asks the narrator if he
"had no feeling that they [the narrator's words] were conveyed to you in a supernatural way?"
The next night, the signalman confides to the narrator that the previous night he had mistaken the narrator for "that someone else." This person puts his left arm across the face and waves violently with the right arm. He has heard this man cry, too. But, the empirical narrator explains this vision to the signalman,
...I showed him how that this figure must be a deception of his sense of sight; and how that figures, originating in diseas ofthe delicate nerves that minister to the functions of the eye, were know to have often trouble patients,...and even proved it by experiments upon themselves.
The narrator explains the "imaginative cry" as voices in the unnatural valley that play upon the "wild harp" of the telegraph wires. The signalman tells the narrator that he has not finished his tale:
Within six hours after the Appearance, the memorable accident on this Line happened, and within ten hours the dead and woounded were brought along through the tunnel over the spot where the figure had stood.
Further, he informs the narrator that this incident occurred about a year ago. But, six or seven months have passed, and one morning in the predawn, he has seen the spectre again. And, again, the empirical narrator asks him questions. The signalman says that the ghost left.
For everything that the signalman says, the narrator offers a logical explanation. However, the signalman tells the narrator that he noticed someone waving hands, and he later learned that a young lady had died in one of the compartments. After a week, the spectre returned and resumed his calling out to "Look out! Look out!" Convinced of his error, the narrator says that the bell has not rung, but the man insists that the bell's ring is "a strang vibration."
After the narrator makes the man look out the door for the spectre, who is not there, the signal-man asks, "What is the danger? Where is the danger?" feeling "some dreadful calamity." The narrator departs the nervous signalman, sensing something eerie himself. Then, the narrator believes that he will ask a wise practioner about him.
The next evening, the narrator takes a stroll, but is taken aback when he sees the
"appearance of a man, with his left sleeve across his eyes passionately waving his right arm."
Somehow, the signalman had not heard the train and has been killed. The strange supernatural warnings were for the signalman. Most shaken by the death of his new friend and the nature of the accident as exactly as described by the signalman, the narrator abandons his rational thought when he is told by the engineer that he hears the words that the signalman has mentioned as well as the words which the narrator has "attached, and that only in my own mind, to the gesticulation he had imitated."
Somehow, these supernatural incidents have happened. With the train's having disturbed nature with the carving of the hill, supernatural forces have been unleashed and set in motion, too strong to be controlled.