He had to clutch the brake-wheel to keep himself from falling.
Si walked to the end of the car, tore off the brake-wheel, and came back.
The fireman had already seen the danger, and sprung to the brake-wheel on the tender behind him.
He turned then to the brake-wheel, but, before he could apply it, Thomson had risen and grappled with him.
Another element sometimes employed in arc-lamp mechanism is the brake-wheel regulator.