Marsden was given the title of Director of Scientific Developments, and was charged with mobilizing New Zealand's scientific manpower. During the War he worked on radar research, setting up a team to develop the radar equipment for use in the Pacific. Marsden also used his scientific connections to form a team of young New Zealand Scientists who would participate in the American Manhattan Project developing the nuclear bomb, and initiated the search for uranium, the raw material needed for nuclear projects, in New Zealand. Marsden had a post-war vision of a nuclear New Zealand, with scientists working on research using local nuclear reactors, and developing connections with the British nuclear energy and weapons program. While this vision was not fully realised, in 1946 he established a team of scientists to carry out research into atomic energy and the application of nuclear science to problems in agriculture, health, and industry. Ties between Marsden and the scientific community in Britain remained strong, and in 1947 he became the DSIR's scientific liaison officer in London. Marsden retired in 1954 and returned to Wellington, where he continued to work and travel extensively, serving on a number of committees and conducting research into environmental radioactivity. As his studies turned to the impact of fallout from radioactive bombs, Marsden came to oppose testing and the development of nuclear weapons. While Marsden had a significant role in establishing and encouraging nuclear science in New Zealand, this role of speaking out against nuclear weapons development and testing - which he only did after the British nuclear testing program was complete - is less known. In 1966, the same year France began testing nuclear bombs in the Pacific, Marsden suffered a stroke which left him confined to a wheelchair. He later died at his home in Lowry Bay, Lower Hutt on the shores of Wellington Harbour in 1970. Family life Marsden married Margaret Sutcliffe, a school teacher, in 1913. They had two children together, a son and a daughter. After Marsden's final retirement to New Zealand, Maggie (who had been suffering from heart disease) died on 7 November 1956. Two years later Marsden remarried, and on 26 June 1958 Joyce Winifred Chote, who was 30 years his junior, became his wife. She assisted him in his remaining years, joining him on his travels and supporting him during his research. Honours and awards Marsden's career recognitions included fellowship in the