on the hill to the north of the main ring, were moved to the valley on the northwest side of the railway, their place being taken by machinery exhibits. The hill has since been known as Machinery Hill and the valley as Sideshow Alley. In 1909, the year of the Jubilee Exhibition (celebrating 50 years since the separation of Queensland from New South Wales), the Exhibition Grounds were extended with the acquisition of Petty's Paddock, an adjacent bounded by Gregory Terrace and Alexandria, Science and Water Streets, purchased for . Around 1910, a two-storey timber building with pressed metal ceilings and a prominent roof fleche, was erected along the northern side of Gregory Terrace near the main entrance. A section of this building was utilised as a Post Office by August 1933. During the First World War (1914–18), a military recruiting and training camp, complete with a rifle range, was established at the Exhibition Grounds, but this did not prevent the annual Exhibition from proceeding. In the 1910s, Brisbane architects Richard Gailey snr and Richard Gailey jnr established a relationship with the National Association which was to last through the 1920s and 1930s. In May 1914, they called tenders for the construction of a sheep, pig and poultry pavilion and fencing along Gregory Terrace and in 1917 for timber dog and horse pavilions. In 1917, Toowoomba's Austral Hall (designed by architect William Hodgen and erected in 1904) was purchased for and re-erected at the Brisbane Exhibition Grounds. It was the largest building of its type in Queensland. Reflecting the growing popularity of the motor car, the pavilion was occupied by representatives of the local automobile trade. It was the first Brisbane Exhibition pavilion to be dedicated solely to motor vehicle displays, automobile exhibits previously being located on Machinery Hill. In 1919 Austral Hall was renamed the John Reid Pavilion following the death that year of Brisbane merchant John Reid, a long-time supporter of the National Association. Affleck House was completed by August 1918 for the showtime use of Stock Breeders' Association delegates. It was named after National Association councillor WL Affleck, who raised the finance for the construction. During the influenza epidemic which swept Australia in 1919, following the return of service personnel from overseas at the end of the First World War, army huts were erected at the exhibition grounds as isolation wards for the nearby Brisbane General Hospital,