leg, the two following Australians were overwhelmed, losing by nine seconds, with the Americans setting another world record. Physiologists had become involved in sport at the time of the Paris Olympics and Charlton's lung capacity was tested with a machine, which blew mercury through a set of bent tubes. They could not believe his lung capacity. It was the highest lung capacity of anyone they had rated at that time – only 16 years of age. After the games, Charlton declared that swimming would take a back seat to his study and work career, and declined offers to tour the US and Europe. However, he still won the 200 m, 400 m and 800 m events at the Tailteann Games. He resumed studies at Hawkesbury Agricultural College, but did not graduate and subsequently became a station-hand at Kurrumbede station in Gunnedah, in western New South Wales. Charlton limited his training to irregular visits to Sydney, when he consulted his coach, former Olympic medallist Henry Hay. After a two-year absence from competition, he returned to the New South Wales championships in 1927, setting a world record of 10m 32s in the on his return. He was again victorious in the in an Australian record time of 4 min 59.8 s. Charlton again returned to his inland job in Gunnedah before returning to Sydney the following year to secure qualification for the 1928 Summer Olympics in Amsterdam by winning the New South Wales championships. In Amsterdam, in the 1500 m, Charlton finished second behind Borg in his heat, before trailing Buster Crabbe home in the semi-final. Borg went on to set a new Olympic record to defeat Charlton by 15 m. In the 400 m, Charlton again finished second in both his heat and semi-final. He again claimed the silver medal, finishing behind Argentina's Alberto Zorrilla. In total, Charlton won five Olympic medals, which was a record until 1960. After shelving his swimming career on his return to Australia for four years, Charlton again broke the Australian record in both the 440 and freestyle events at the 1932 New South Wales championships to gain selection for the 1932 Summer Olympics in Los Angeles, the oldest member of the team at 25 years of age. He contracted influenza a fortnight before the Games after arriving in the United States. Charlton raised hopes that he had recovered when he won his heat, but then