from The Century Dictionary and Cyclopedia
- n. A device consisting of a small wheel with a smooth periphery which bears against the face of a smooth disk.
Sorry, no etymologies found.
Such motion may be produced by the spring, i, and its extent is such that the drum, g, is brought in contact with the friction-disk, e.
_ab_ is the shaft having a continuous rotary motion, and upon which are fixed the pulley, c, the fly-wheel, d, and the friction-disk, e.