Menai Suspension Bridge was completed and opened in January 1826, a triumph for Thomas Telford and the longest span in the world. Despite the success of the bridge Telford was not entirely happy and was concerned by perceived problems. During construction the bridge suffered damage in strong winds and in February 1826 six hangers broke. Breakage of six hangers was repeated again in 1836 and in 1839 the deck was virtually wrecked in a hurricane. Provis was engaged to consider the matter and designed a new, articulated and heavier deck for the bridge, the construction of which was supervised by Maude. The replacement timber deck survived until 1893 when Baker designed a new steel deck. In 1908, Rivers commenced repairs and modifications to the bridge, but these were not entirely satisfactory. Tudsbery and Gibbs were engaged to examine the bridge in 1922, and it was recognised that the carriageway and weight restrictions severely limited use of the bridge. In 1938, Dorman Long began the difficult task of reconstructing the bridge to carry the full spectrum of modern road traffic. This paper recalls the first 112 years of the history of the bridge up until the time of the reconstruction.

The bearings of Menai Suspension Bridge represent a significant development in the understanding of structures and of the mechanism of suspension bridges. Thomas Telford's interest in suspension bridges began with studies for Runcorn in 1814, but at a time when little was known. Although a number of suspension bridges were built prior and were contemporary with Menai and Conwy, few survive and most were of largely intuitive design construction. Telford's research identified that it was necessary for the catenary to transmit load into the back spans and that the load in the catenary would vary depending on the live load on the suspended span. If the saddle were fixed, then the loads would be transmitted into the masonry. It was also acknowledged that changes in temperature would also lead to changes in load. To overcome this problem a means was required that would allow the saddle to move freely. The solution was the use of a series of roller bearings located beneath the chain saddles and fixed to the top of the pyramids, Telford's description for the towers. This paper discusses the design of these bearings, how they were incorporated into the catenary and the towers, reports of the bearings in service and the bearing components that survive in the care of Menai Bridge Community Heritage Trust and displayed in the Menai Heritage exhibition in the Thomas Telford Centre.

Menai and Conwy suspension bridges in Wales, both completed in 1826 to Telford's design, represented a significant advance in engineering science and were the culmination of extensive experiment and theoretical study. Telford established practices and procedures during the design and construction of the 177 m span Menai and 100 m span Conwy bridges for experiment, analysis, test and inspection that are recognised to this day as good practice in engineering. The ideas and methods adopted have had a lasting influence upon the profession.

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