As the most basic type of bridge, a beam bridge bears the load between its supports. Beam bridges can be as simple as a fallen tree trunk across a stream and as complicated as Quebec City's cantilever bridge, spanning 1,800 feet to become the longest of its kind in the world.
Known for their beauty as well as durability, arch bridges have abutments on each side to restrain the horizontal transfer of compression forces. Designed with single or multiple arches, these bridges are built from a variety of materials, from wood to masonry and metal to concrete.
North American Railroad Bridges by 
Elegant Arches, Soaring Spans by Shaped like an inverted arch, suspension bridges use a catenary curve to support the weight of the deck on a variety of materials, ranging from ropes of vine or leather, to chains of iron or cables of high-strength steel.
A Tale of Two Bridges by 
Inspection, Evaluation and Maintenance of Suspension Bridges Case Studies by 
Structural Health Monitoring of Long-Span Suspension Bridges by 
History of the Modern Suspension Bridge by 
Movable Bridge Engineering by When unable to build a bridge high enough to provide clearance for the waterway, it can be more practical to construct a bridge that moves. Three commons designs include the bascule, which pivets upward, the swing bridge, which rotates to the side, and the vertical lift bridge, which goes up and down.
Movable bridge design by A development of recent times, cable-stayed bridges support the weight load by directly running the cables from the deck to plyons.
Cable-Stayed Bridges: 40 Years of Experience Worldwide by 
Cable Stayed Bridges by 
Advances in Cable-Supported Bridges by 
Cable Supported Bridges: Concept and Design by 
Wind Effects on Cable-Supported Bridges by 
Scherzer Rolling Lift Bridges [Catalogue]. Chicago: The Scherzer Rolling Lift Bridge Company, 1908.
Call Number: TG 420.S33 1908 ESL Rare Book Cage
Atlas to the Life of Thomas Telford, Civil Engineer. Edited by John Rickman. London: Payne and Foss, 1838.
Call Number: QP 18A Rare Book Room
Four suspension bridges were intially proposed for the location of the Forth Bridge. Construction had begun on one design, by Sir Thomas Bouch, prior to the collapse of another one of his works, the Tay Bridge (1879). Here are the preliminary designs for those suspension bridges:
After the disgrace of Sir Thomas Bouch, another bridge was designed, by Sir John Fowler and Sir Benjamin Baker, with stability as top priority. Still regarded as an engineering marvel, the Forth Bridge is now the second longest single-span cantilever bridge in the world. Here are the proposed and final designs of this bridge, the first major steel structure to be built in Britain:
The Forth bridge / Reprinted from "Engineering", February 28, 1890 by W. Westhofen. London: Offices of Engineering, [1890?].
Call Number: TG 64.F7 W4 folio Rare Book Cage
Atlas to the Life of Thomas Telford, Civil Engineer. Edited by John Rickman. London: Payne and Foss, 1838.
Call Number: QP 18A Rare Book Room