depression. At the time he had two young children, and a responsible job at a factory where accidents could and did have terrible consequences. He travelled and became a public figure. But the memory of what happened less than twenty years earlier still burned in his mind. Today the link between such trauma and depression is better understood. Doctors prescribed several different drugs over the years, but these had variable efficacy and side effects. In 1964 Levi collaborated on a radio play based upon If This Is a Man with the state broadcaster RAI, and in 1966 with a theatre production. He published two volumes of science fiction short stories under the pen name of Damiano Malabaila, which explored ethical and philosophical questions. These imagined the effects on society of inventions which many would consider beneficial, but which, he saw, would have serious implications. Many of the stories from the two books (Natural Histories, 1966) and (Structural Defect, 1971) were later collected and published in English as The Sixth Day and Other Tales. In 1974 Levi arranged to go into semi-retirement from SIVA in order to have more time to write. He also wanted to escape the burden of responsibility for managing the paint plant. 1975–1987 In 1975 a collection of Levi's poetry was published under the title (The Bremen Beer Hall). It was published in English as Shema: Collected Poems. He wrote two other highly praised memoirs, (Moments of Reprieve, 1978) and (The Periodic Table, 1975). Moments of Reprieve deals with characters he observed during imprisonment. The Periodic Table is a collection of short pieces, based in episodes from his life but including two short stories that he wrote while employed in 1941 at the asbestos mine in San Vittore. Each story was related in some way to one of the chemical elements. At London's Royal Institution on 19 October 2006, The Periodic Table was voted onto the shortlist for the best science book ever written. In 1977 at the age of 58, Levi retired as a part-time consultant at the SIVA paint factory to devote himself full-time to writing. Like all his books, La chiave a stella (1978), published in the US in 1986 as The Monkey Wrench and in the UK in 1987 as The Wrench, is difficult to categorize. Some reviews describe it as a collection of stories about work and workers told by a narrator