1957, signs of the cancer that would kill Dalton in 1961 were apparent. Although the cause of death is generally acknowledged, and her belief discounted by informed contemporaries, in her book Without Hardware Catherine Dalton alleged that her husband was murdered; she claimed that the Bogle-Chandler deaths were intended to prevent Bogle, a friend of Dalton's, from investigating her husband's death. Catherine considered that her husband subjected his family to a "regime of parsimony and neglect", and claimed after his death that, as early as 1955, she had detected what she considered his "schizophrenic behaviour", leading to "caprice and violence" in his private life in stark contrast to the admirable man his colleagues considered him to be. She refused to divorce or leave Dalton, attributing his illness to poisoning by "malevolent elements of the intelligence community". References 1961 deaths 1916 births New Zealand nuclear physicists Royal Air Force Volunteer Reserve personnel of World War II Royal Air Force squadron leaders Deaths from cancer in New South Wales Graves family