This book represents collaboration, not least because its eight chapters are the work of twelve people whose expertise covers engineering, historical archaeology, economic history, and the history of place. Despite very different professional backgrounds, they share a keen interest in a remarkable feature of New South Wales, the timber truss bridges that have been part of the landscapes of NSW for over 100 years.
Over 400 timber truss road bridges were built in New South Wales between 1856 and 1936. Some of the 51 standing today will need to be replaced within the next 20 years, leaving less than 30 remaining into the future as rare and representative examples, a heritage of the State. Aesthetically pleasing in their scale, proportion and materials, the timber truss bridges of New South Wales also demonstrate engineering and technical excellence. Allied to local knowledge and discovery, this made possible the use of superb local timbers to create enduring bridge crossings. Using readily available local materials and avoiding wherever possible the expensive imported materials, construction of these bridges stimulated and supported the development of local industries. They demonstrate some of the unique qualities of the New South Wales hardwoods, plentiful at the time.
This book records the history of the timber truss bridges of New South Wales so that everyone can recognise what each bridge represents. These chapters draw together elements of engineering design, technical aspects of materials and construction, and the long-term performance of bridges, with a close look at history, at the people and places that are an integral part of the story of these bridges.
In Chapter 1, ‘The early years’, the foundations of bridge building in colonial New South Wales are investigated by Tony Brassil, Lenore Coltheart and Rex Glencross-Grant. They discover some unexpected effects of the commonplaces of colonial history, the convict decades, responsible government, the periods of prosperity and of economic depression. Their inventory of these effects includes for instance a reason why timber bridges supplanted masonry; the link between votes and bridges, and introduces some odd players in the timber truss story, like bullocks, traction engines and tabletop wagons.
Don Fraser and Amie Nicholas detail the history of the timber truss in Chapter 2, ‘Developing the truss’. In an absorbing account, they trace the story from the roofs of Renaissance Venice to the rivers of New South Wales. They show the engineering ingenuity of each of the five distinct truss types named for the leading engineers whose work they were, William Bennett, John McDonald, Percy Allan, Ernest de Burgh and Harvey Dare. These men and their families are the subject of Chapter 3 ‘The designers’, where Lenore Coltheart finds new clues to their lives and times. In adding to each portrait the tragic, heroic, sardonic, proud, charming, and persevering traits discovered, a richer understanding of the design achievement is uncovered.
In Chapter 4, ‘Timber truss technology’, Ian Bowie traces the origins of the timber truss bridge even further, making an intriguing link between the Roman Empire of the 2nd century and the engineering laboratories of the University of Sydney in the 1880s. In the same chapter Amie Nicholas takes a microscope to the timbers of New South Wales, showing how local hardwoods came to be rated among the strongest and most durable in the world and offering a glimpse into the future of timber engineering.
Ian Jack covers the social pages in Chapter 5 ‘People, places and bridges’, weaving a vivid tapestry of local communities lobbying for their bridges and celebrating their triumphs. There are banquets and balls, picnics and processions; but beneath each centrepiece of a brand new bridge decorated with foliage and flowers, flow the undercurrents of rivalries and disappointments. The bridge builders themselves are introduced by Ian Berger in Chapter 6. The skills passed from fathers to sons as families followed the work from small towns to remote rivers are assessed, while the stories of success and failure offer rare insights into both the building processes, and the bridges.
Chapter 7, ‘Weighty matters’, introduces three modern-day bridge engineers, Brian Pearson, Ray Wedgwood and Wije Ariyaratne, between them covering more than half a century of looking after the State’s timber truss bridges. In conversation with Amie Nicholas, they provide a lively and unique account of their work and their admiration for both the bridges and their designers.
Denis Gojak reflects on how the heritage of the timber truss bridges of New South Wales came to be recognised, in Chapter 8, ‘A working legacy’. It took remarkable people and a change in the understanding of heritage in Australia before the significance of these bridges was recognised. The outstanding photographs in this chapter and throughout the book offer the opportunity to ‘read’ the heritage values of the bridges, as well as to recognise the stories each represents.
Their distinctive association with New South Wales gives the timber truss bridges significance for the State, while the role of each in its particular place provides an intimate association with local identity. The designs of the bridges reflect the ingenuity of the original designers, all of them internationally recognised engineers. Working together or in sequence, they built on each other’s ideas and expertise, with the bridge builders also contributing to the body of knowledge that produced the engineering and technical excellence demonstrated in the five types of timber truss bridges used on roads in New South Wales. As this book shows, most of all these bridges stand for the value of collaboration.