Historical. In the year 1862 the construction of a traffic bridge over the estuary of the Swan River at Fremantle, Western Australia, was commenced. This bridge, which was constructed of Jarrah (Euc. marginata) and entirely by convict labour, generally employed in chain gangs, was completed and opened for traffic in 1866. In 1908, after 42 years' service, the bridge was reconditioned and at this time, 306 out of the 319 Jarrah piles were found to be in a sound and serviceable condition. Since its construction it has now given excellent service for over seventy years. As this bridge lies on the main Perth-Fremantle highway, it receives heavy and continuous traffic, and in June, 1937. it was condemned and decided that a new bridge should be erected. Of recent years much controversy has existed with regard to the relative merits of timber versus steel and concrete for structural work, and it is interesting to note that after due consideration, the Western Australian Government approved of a timber design uti...