A man named Toby Dammit was known for his bad habits and vices, which were attributed to his mother's left-handedness. As a child, he was constantly punished by his mother, but her left-handed beatings only seemed to make him worse. As he grew older, his vices increased, and he developed a habit of making bets on everything, often saying, "I'll bet the Devil my head."
One day, the narrator and Dammit went for a walk and came across a bridge with a turnstile. Dammit insisted on leaping over the turnstile, and the narrator, doubting his ability, called him a braggart. Dammit then offered to bet the Devil his head that he could do it.
I'll bet the Devil my head.
As they prepared for the leap, a little old gentleman appeared and agreed to the bet, saying it was just a formality.
Dammit attempted the leap, but instead of clearing the turnstile, he landed on the same side he started from, having collided with a horizontal iron bar above the turnstile. The old gentleman quickly grabbed Dammit's severed head and disappeared. The narrator, realizing the seriousness of the situation, took Dammit home and called for medical help.
Unfortunately, Dammit did not survive his injury, and the narrator mourned his friend's death. He sent a bill for the funeral expenses to a group of transcendentalists, who refused to pay. In response, the narrator had Dammit's body exhumed and sold for dog meat.