Cash was sent as a convict to Sydney, sailing in the ship "Marquis of Huntley". He was sent to work for George Bowman in the Hunter River area. After being set free, he continued to work for Bowman. He was suspected of stealing cattle so he left New South Wales and went to Van Diemen's Land with Bessie Clifford and arrived in February 1837. In 1839 he was again convicted of stealing and sent to prison for seven years. During the next three years he escaped three times. He nearly escaped from Port Arthur by swimming. He was given an extra four years in prison at Port Arthur.