[CHÂTEAU DE LA MUETTE] [Manufacture ÉRARD]. Printed prospectus, January 1856 (in-4 on blue paper) Prospectus of Pierre Érard's Forte-Pianos factory, with a list of the different pianos: grand or square with double escapement; upright pianos with oblique or perpendicular strings; harps, with sales prices; and reproduction of the medals won at the Universal Exhibitions. A bronze medal of honor won at the 1855 World's Fair is attached; these medals were placed inside the pianos. D : 7,5 cm