Wetterleuchten der Revolution / Eva Broido. Berlin: Der Bücherkreis, 1931
“Dustjackets were only added to copies of Bücherkreis books that were sold in shops (not those sent to members) in order to satisfy the need for window display. Despite much individual variation, Tschichold developed a theme for the jackets whereby what would today be called the blurb, a short paragraph summarizing the book’s content, was featured on the front cover, whereas it would commonly be printed inside the front flap or on the back. This not only gave Tschichold more elements for his composition, given that purely typographic jackets were undoubtedly a necessity due to the cost of photographic reproduction, but also served to emphasize the subjects of the books, which were a prime consideration for the Bücherkreis”.
Christopher Burke. Active literature: Jan Tschichold and New Typography. London: Hyphen Press, 2007 (p. 215)