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The nation's oldest all-metal railroad bridge still in use is here in Halls Station (also known as Halls). It has a pony Howe truss, which differs from the Howe truss in having all-metal members, not only for the tension members (verticals) but also for the compression members (diagonals), which are of hollow cast iron rather than wood. Fear of arson from economically threatened canal boatmen led the railroad to shift from timber bridges to fireproof iron bridges. Experience soon showed, however, that cast iron did not provide enough strength for compression members, and the pony Howe truss was abandoned for railroad bridges before the Civil War. This bridge is sixty-nine feet long and its crossing diagonal members were cast in an Egyptian Revival lotus-blossom design and connected to the wrought-iron upper and lower chords with a unique pinning system. It was moved to its present site to handle vehicles crossing the railway tracks to a farm. The railroad was built in 1871–1872 as the Catawissa Railroad, which terminated in Williamsport. In 1884, the failing Catawissa line was acquired by the Philadelphia and Reading Railroad, which in turn was absorbed by Conrail in the 1970s, and in 1996 became the Lycoming Valley Railroad. Richard B. Osborne, chief engineer of the Philadelphia and Reading Railroad, designed and built at least two other all-metal railroad bridges in the 1840s, one in West Manayunk, Pennsylvania (a piece of which is now in the Smithsonian Institution), and another near Reading (now at the Railroaders Memorial Museum in Altoona).