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"A pair of runners connected by a framework, used (sometimes with another pair) to carry loads or support the body of a vehicle, or, when of lighter build and supporting a light platform or seat, in the sport of coasting and for drawing light loads by hand. A, bob-sled, composed of two short sleds a, a1 connected by a perch b, which is attached to the sled a1 by a king bolt c, on which the sled a1 turns freely, thereby enabling it to be turned around in a space a little wider than its own length: the box or body of the sled, when one is used, is supported on the bolsters d, d1." —Whitney, 1889

Bobsled - Side View

"A pair of runners connected by a framework, used (sometimes with another pair) to carry loads or support…