An advertisement for the 1930 S.A.T. Congress in London. Esperanto has been in regular use now for 123 years, while the body organising this event appeared a generation later, in 1921, during a period of great revolutionary enthusiasm. The ´Sennacieca Asocio Tutmonda´ (SAT - the World Transnational Association), the association for worker Esperantists committed to social justice and cultural innovation. This poster was most likely realized using the woodcut technique, a relief printing artistic technique in printmaking in which an image is carved into the surface of a block of wood.