Wine glass with the arms of Johan de Back; Chalice with the arms of Johan de Back; secretary and secret council of William IV; Vaulted foot. Slim baluster stem with knots and air bubbles. On the conical chalice the coat of arms of Johan de Back (1698-1766); secretary and secretary of Stadholder Prince William IV. On the back text: De.HEER.GEHEYMRAAD.EN./ SECRETARY.VAN.SYN./ HOOGHYDT.DE.BACK; armorial bearing; heraldry; Johan de Back; Willem IV (Prince of Orange-Nassau); anonymous; c. 1750 - c. 1766; glass; glassblowing; h 18.5 cm x d 8.1 cm