Here we have the story of the Montgolfier brothers and their struggle to invent and perfect the first balloon. They learn that ""nothing is so simple as what was done yesterday; nothing so difficult as what is to be done tomorrow"". The book opens with a crowd of awed Southern French townspeople staring up at the young inventor who is about to jump from his roof-top with an early form of parachute, in this way the young readers attention is caught immediately. One brother is the shy genius, the other the practical man of affairs, which make a well balanced pair. There are graphic accounts of the trial flight with its cargo of hen, duck and lamb and the later flight over Paris with humans aboard. Our beloved Franklin enters the picture occasionally and there are good impressions of the court of Louis XVI.