What happens when Ichabod tries to get across the bridge in "The Legend of Sleepy Hollow"?

On his ride home in "The Legend of Sleepy Hollow," Ichabod Crane's mount, Gunpowder, comes to an abrupt stop at a bridge. The horse jumps sidewise when kicked; kicked again, he jumps the other way into bushes. Then, Icabod sees the dark, ominous figure. Ichabod asks, "Who are you?' and, after no answer, the figure appears, looking like a large horseman mounted on a powerful black horse. He jogs along the blindside of old Gunpowder, who has overcome his fright. When the mysterious companion runs upon a rise in the ground, Ichabod sees against the lighted sky that the horseman had no head. Instead, the head is carried on the pommel of the saddle. Ichabod takes off, but the other keeps pace. Suddenly, Gunpowder turns, plunging down the hill on the left, the saddle girth breaks and Ichabod clings to the horse's neck as it bounces him in its flight. As Ichabod crosses the church bridge, the goblin rises in the stirrups and hurls his head at him. It hits Ichabod, sending him into the dust. Gunpowder, the black steed, and the goblin pass by Like a whirlwind.