A popular material for trusses and trestles in the 1800s, also used for covered bridges.

• A. Stone
• B. Wood
• C. Concrete
• D. Steel

Answer: (B)

Wood is the material that best fits here because in the 1800s most trusses and trestles were built from large timber members. Timber could be cut, shaped, and joined with simple tools and pins on site, making it practical and economical for frequent, long spans without sophisticated factories. Covered bridges were specifically designed with a roof and siding to protect these wooden members from rain, snow, and decay, dramatically prolonging the life of the structure. While stone and later steel or concrete were available, they weren’t the standard choice for typical 19th-century truss and trestle bridges, and the popularity of wood for covered bridges reflects its availability, workability, and the protective purpose of the coverings.