On October 22, 1934, in a famous experiment, Enrico Fermi and his colleagues discovered that a significant increase in induced radioactivity can be obtained when neutrons are slowed down by means of hydrogen atoms. This discovery and its explanation earned him the 1938 Nobel Prize in Physics. One year later, on October 1935, Fermi held a public speech in Palermo, Italy, presenting his findings at the 24th congress of the Italian Society for the Progress of Sciences. The transcription of his s...