In the early 20th century J. W. Dunne, a British aeronautics engineer, experienced several dreams which he regarded as precognitive. He developed techniques to record and analyse them, identifying any correspondences between his future experiences and his recorded dreams. He reported his findings in his 1927 book "An Experiment with Time". In it he alleges that 10% of his dreams appeared to include some element of future experience. He also persuaded some friends to try the experiment on themselves, with mixed results. Dunne concluded that precognitive elements in dreams are common and that many people unknowingly have them. He suggested also that dream precognition did not reference any kind of future event, but specifically the future experiences of the dreamer. He was led to this idea when he found that a dream of a volcanic eruption appeared to foresee not the disaster itself but his subsequent misreading of an inaccurate account in a newspaper. In 1932 he helped the Society for Psychical Research to conduct a more formal experiment, but he and the Society's lead researcher Theodore Besterman failed to agree on the significance of the results. Nevertheless, the Philosopher C. D. Broad remarked that, "The only theory known to me which seems worth consideration is that proposed by Mr. Dunne in his Experiment with Time."