Paris: Librairie de la Construction Moderne, 1926. Interesting treatise on the theory and practice of sundials, and how shadows work. In French. Large format softback covers. A little darkening to the covers and slight nicking to the edges. Internally clean throughout with just a touch of darkening to the pages. viii, 1-274 pp. 360 x 285 mm (14¼ x 11¼ inches).