Hiram W. Merrill (1822-1898) of Plymouth, N. H., built Blair Bridge in 1870 to replace a span of 1829 that had been burned by an arsonist. The bridge employs a truss design patented by Col. Stephen Harriman Long (1784-1864) of Hopkinton, N. H. It is New Hampshire's only surviving example of Long's patent to retain wedges at the lower chords by which the trusses were pre-stressed during construction, stiffening the bridge against the weight of traffic. Covered bridge expert Milton S. Graton (1908-1994) restored the structure in 1977.

Photo: cmh2315fl via Flickr (CC BY-NC 2.0)

Photo: cmh2315fl via Flickr (CC BY-NC 2.0)

Campton, New Hampshire · USA