thoroughbrace

1. (dated or historical) A leather strap supporting the body of a coach or wagon, attached to springs or serving as a spring itself.Examples: "Spring, tire, axle, and linchpin too, Steel of the finest, bright and blue; Thoroughbrace bison-skin, thick and wide; Boot, top, dasher, from tough old hide Found in the pit when the tanner died."; "The wagon-bed is supported by iron bands or perpendiculars abutting upon wooden rockers, which rest on strong leather thoroughbraces: these are found to break the jolt better than the best steel springs, which, moreover, when injured, can not readily be repaired."; ""Why, it happened by trying to make one coach carry three days' mail—that's how it happened," said he. "And right here is the very direction which is wrote on all the newspaper-bags which was to be put out for the Injuns for to keep 'em quiet. It's most uncommon lucky, becuz it's so nation dark I should 'a' gone by unbeknowns if that air thoroughbrace hadn't broke.""datedhistorical