He wrote a great deal but built very little in the late 1930s. The titles of his books expressed the combined urgency and optimism of his messages: "Cannons? Munitions? No thank you, Lodging please!" (1938) and "The lyricism of modern times and urbanism" (1939). In 1928, the French Minister of Labour, Louis Loucheur, won the passage of a French law on public housing, calling for the construction of 260,000 new housing units within five years. Le Corbusier immediately began to design a new type of modular housing unit, which he called the Maison Loucheur, which would be suitable for the project. These units were in size, made with metal frames, and were designed to be mass-produced and then transported to the site, where they would be inserted into frameworks of steel and stone; The government insisted on stone walls to win the support of local building contractors. The standardisation of apartment buildings was the essence of what Le Corbusier termed the "Ville Radieuse" or "radiant city", in a new book which published in 1935. The Radiant City was similar to his earlier Contemporary City and Plan Voisin, with the difference that residences would be assigned by family size, rather than by income and social position. In his 1935 book, he developed his ideas for a new kind of city, where the principle functions; heavy industry, manufacturing, habitation and commerce, would be clearly separated into their own neighbourhoods, carefully planned and designed. However, before any units could be built, World War II intervened. During the War and the German occupation of France, Le Corbusier did his best to promote his architectural projects. He moved to Vichy for a time, where the collaborationist government of Marshal Philippe Petain was located, offering his services for architectural projects, including his plan for the reconstruction of Algiers, but they were rejected. He continued writing, completing "Sur les Quatres routes" (On the Four Routes) in 1941. After 1942, Le Corbusier left Vichy for Paris. He became for a time a technical adviser at Alexis Carrel's eugenic foundation, he resigned from this position on 20 April 1944. In 1943, he founded a new association of modern architects and builders, the Ascoral, the Assembly of Constructors for a renewal of architecture, but there were no projects to build. When the war ended, Le Corbusier was nearly sixty years old, and he had not had a single project realized in ten years.