Watch List notes:

The Portland Collection, Commemorative Medals, Ballooning: France, the Montgolfier Brothers, First Demonstration Flight of a Hydrogen Balloon, from the Champ de Mars, copper medal, 1783, by N. M. Gatteaux, conjoined windswept busts l., ... POUR AVOIR RENDU L'AIR NAVIGABLE, rev. the balloon ascends above rain clouds on the Champ de Mars, watched by large crowds, 42mm. (Malpas 3; BDM.II, 210), very fine, scarce
Joseph Montgolfier (1740-1810) and Etienne Montgolfier (1745-1799).