one of 80 candidates, he spent three months taking lectures, and in February, after passing his colloquio (oral examination), he was selected as one of 20 to move on to the full-time chemistry curriculum. In the liberal period as well as in the first decade of the Fascist regime, Jews held many public positions, and were prominent in literature, science and politics. In 1929 Mussolini signed an agreement with the Catholic Church, the Lateran Treaty, which established Catholicism as the State religion, allowed the Church to influence many sectors of education and public life, and relegated other religions to the status of "tolerated cults". In 1936 Italy's conquest of Ethiopia and the expansion of what the regime regarded as the Italian "colonial empire" brought the question of "race" to the forefront. In the context set by these events, and the 1940 alliance with Hitler's Germany, the situation of the Jews of Italy changed radically. In July 1938 a group of prominent Italian scientists and intellectuals published the "Manifesto of Race," a mixture of racial and ideological antisemitic theories from ancient and modern sources. This treatise formed the basis for the Italian Racial Laws of October 1938. After its enactment Italian Jews lost their basic civil rights, positions in public offices, and their assets. Their books were prohibited: Jewish writers could no longer publish in magazines owned by Aryans. Jewish students who had begun their course of study were permitted to continue, but new Jewish students were barred from entering university. Levi had matriculated a year earlier than scheduled enabling him to take a degree. In 1939, Levi discovered his passion for mountain hiking. A friend, Sandro Delmastro, taught him how to hike, and they spent many weekends in the mountains above Turin. Physical exertion, the risk, and the battle with the elements while following Sandro's example enabled him to put out of his mind the nightmare situation precipitating all over Europe as, communing with the sky and earth, he managed to satisfy his desire for liberty realize fully his own strength, and the reasons behind his ardent need grasp the nature of things that had led him to study chemistry, as he later wrote in the chapter "Iron" of The Periodic Table (1975). In June 1940 Italy declared war as an ally of Germany against Britain and France, and the first Allied air raids on Turin began two days later.