| Historical notes: | SETTLEMENT OF NORTHERN SYDNEY
Settlement in the northern parts of Sydney was slow because of the rocky terrain. The Great Northern Road opened the area from Pennant Hills to the Hawkesbury River between 1826 and 1832. Construction of the northern railway from the early 1880s provided access to the eastern area from Strathfield to Hornsby and then on to Brooklyn on the Hawkesbury River.
Land grants were developed as farms and by the mid-19th century the areas from Parramatta to Pennant Hills and on to Dural and Galston featured many orange orchards. Fruit growers took their produce to markets in Sydney and to the harbour for export. Initially, carts travelled to the Ermington wharf on the Parramatta River. Other orchardists drove directly to the city market via Parramatta or to the ferries at Lane Cove or North Sydney. As the railway moved north, orcharding expanded to grow soft fruits such as peaches and apricots which could be carted to the new rail sidings at Pennant Hills and Epping (Schofield, 1988).
JOHN MCDONALD AND THE MCDONALD TRUSS BRIDGES
John Alexander McDonald (1856-1930) was a civil engineer whose work within the NSW Public Works Department (PWD) shaped the development of late 19th century bridge design in NSW. Born in London, he studied engineering at King’s College before gaining experience on engineering projects in England. McDonald migrated to NSW in 1879 to oversee the erection of iron bridges across the Parramatta River and Lane Cove River. He subsequently joined the PWD as an engineering draftsman and progressed steadily through the department, eventually becoming Chief Engineer for Bridges between 1889 and 1893.
McDonald’s 14 year tenure in the PWD coincided with a period of structural innovation and the increasing formalisation of bridge design standards in NSW, during which he led the development of more consistent approaches to timber bridge design. In particular, he drew on emerging technical research and the growing body of Australian experience with local hardwoods. His work intersected with timber testing programs undertaken at the University of Sydney, which provided data on the strength and structural properties of native timbers. This research informed his refinement of timber truss systems and supported the program of standardisation that led to the development of the McDonald Truss, the second stage in the sequence of standardised truss bridges adopted in NSW.
By the early 1890s the PWD had adopted the McDonald truss as its standard form for timber truss bridge construction. The department’s preference for timber reflected the abundance of high quality hardwoods across NSW and the comparative cost of masonry and iron structures during this period. Timber truss bridges provided economical, durable and straightforward construction options suitable for both major routes and remote locations. Standardisation also allowed designs to be adapted efficiently to a wide range of sites while maintaining reliable performance.
Approximately 90 McDonald truss bridges were constructed in NSW between 1886 and 1894, making it one of the dominant types of road bridge during those decades. Their use extended across regions where economical construction and ease of erection were necessary, including areas of rugged or confined terrain. This made it well suited to challenging terrain such as the steep descent into Galston Gorge, where accessible, cost-effective construction was essential.
Following his retrenchment from the PWD in 1893 during departmental staff reductions, McDonald continued his engineering career on harbour, wharf and structural projects in Western Australia, South Africa and New Zealand. He later settled in Gisborne, New Zealand, where he died in 1930 at the age of 70 (Coltheart and Nicholas 2018).
BRIDGE OVER TUNKS (PEARCES) CREEK
Fruit growers in Dural and Galston were frustrated by the lack of access to the new railway at Hornsby. There was a foot track between the two settlements, but it was a hazardous five-mile trek. The creeks at the bottom of the gorge could only be crossed by negotiating fallen trees placed there as rough bridges. Lobbying for a bridge started in the 1880s. Local MPs Frank Farnell (1862 - 1929) and John Nobbs (1845 - 1921) discussed the construction of a bridge on the Galston Road with the Minister for Public Works and in April 1892 he promised £3000 for its construction (Australian Star, 21 April 1892, p. 6).
Two McDonald truss bridges were chosen to span the two creeks at the base of the descent: a larger single span 90’ McDonald Truss crossing Berowra Creek and a smaller single span 65’ McDonald Truss crossing Tunks (Pearces) Creek. Together they represented the largest and smallest of the standard McDonald truss types and functioned as an integrated engineering response to the difficult terrain, carrying the new road across two deep creek gullies in succession (Coltheart and Nicholas 2019).
Galston Road was surveyed by Ebsworth and involved seven hairpin bends zig zagging down the Hornsby side. At the bottom, the two McDonald truss bridges were to be constructed to replace the earlier log crossings. The successful contractor was Francis Boland, who tendered £2,651 10s 6d for construction of the two bridges. Construction works on both bridges began in 1893 and were completed by early 1894. Building materials had to be lowered manually down the steep gorge using ropes and pulleys (Schofield, 1988). Galston Road itself was not completed until 1895 and was officially opened in March of that year by the Minister for Public Works (Cumberland Mercury, 9 March 1895, p. 9).
By 1910 a four-horse coach was carrying the mail from Hornsby to Galston through the gorge and in the late 1930s motor coaches travelled carefully through the hairpin bends between the two settlements (Ollif, 1975). The route through the gorge was, and remains, a challenging one. Passing through picturesque bush scenery, often described as a "miniature Macquarie Pass" in terms of construction and scenery, the Galston Gorge journey became a tourist route for walkers, cyclists and motorists, with the NRMA recommending it as a "fine trip" (St George Call, 20 July 1907, p. 2; Sydney Morning Herald, 17 September 1932, p. 9; Sun, 21 January 1933, p. 8).
In 1937 the larger McDonald truss over Berowra Creek was replaced with a concrete bridge (Daily Telegraph, 11 March 1937, p. 4). Despite this replacement, the route continued to operate as a paired solution to the difficult terrain, with the surviving McDonald truss at Tunks (Pearces) Creek remaining a key structural component in the overall descent and continuing to reflect the engineering responses developed by the Public Works Department in the late 19th century. The bridge has remained in continuous use since its construction and underwent major repair works in 2026 to support its ongoing function within the Galston Gorge route. |