At the beginning of September 1950, while on a short vacation in Italy with his family, Bruno Pontecorvo suddenly disappeared. Nobody knew of him until 4th March 1955, when he gave a press conference in Moscow at the Academy of Sciences where he explained the motivations that had led him to decide to live in Russia. He arrived in Moscow in September 1950 and at the end of October of the same year he moved in Dubna and started his research work at the Institute of Nuclear Problems where, at the time,the most powerful particle accelerator in the world was in operation. A historical reconstruction of the early years of his scientific activity is done through the pages of his first logbook. This “laboratory notebook”, dated November 1, 1950, contains unpublished notes, ideas and considerations that Bruno wrote by hand, mostly in English, at the beginning of his work in Russia
