This chapter is entitled "The years of Pilgrimage". These were the years of World War I, Revolution, Civil War (1914–1925), economic dislocation and the beginning of the 'socialist building". Mandelstam had changed several addresses and several institutions. Mandelstam's letters to R. von Mises help to understand his situation. In Odessa, Mandelstam met I.E. Tamm, who became his disciple.