 Another surviving example, number R 704, was originally displayed at the Festival of Britain in 1951 and is now on permanent display at the Australian Railway Historical Society Museum in Williamstown North, Victoria.Within a few years of the introduction of the A2 class 4-6-0 in 1907, it was clear that increasingly heavy train loads would require a more powerful locomotive on principal main lines.From as early as 1918, a series of drawings for potential 4-6-2 'Pacific' type locomotives began to emerge from the VR's Locomotive Design Section, some of which were ultimately developed into the 3 cylinder S class heavy Pacific of 1928.