Etienne Montgolfier has left us a description of this first balloon. “The aerostatic machine,” he says, “was constructed of cloth lined with paper, fastened together on a network of strings fixed to the cloth. It was spherical; its circumference was 110 feet, and a wooden frame sixteen feet square held it fixed at the bottom. Its contents were about 22,000 cubic feet, and it accordingly displaced a volume of air weighing 1,980 1bs. The weight of the gas was nearly half the weight of the air, for it weighed 990 lbs., and the machine itself, with the frame, weighed 500: it was, therefore, impelled upwards with the force of 490 lbs. Two men sufficed to raise it and to fill it with gas, but it took eight to hold it down till the signal was given. The different pieces of the covering were fastened together with buttons and button-holes. It remained ten minutes in the air, but the loss of gas by the button-holes, and by other imperfections, did not permit it to continue longer. The wind at the moment of the ascent was from the north. The machine came down so lightly that no part of it was broken.” Chapter V. Second Experiment. (Charles’s Balloon, Paris, Champ de Mars, 27th of August, 1783.) The indescribable enthusiasm caused by the ascent of the first balloon at Annonay, spread in all directions, and excited the wondering curiosity of the savants of the capital. An official report had been prepared, and sent to the Academy of Sciences in Paris, and the result was that the Academy named a commission of inquiry. But fame, more rapid than scientific commissions, and more enthusiastic than academies, had, at a single flight, passed from Annonay to Paris, and kindled the anxious ardour of the lovers of science in that city. The great desire was to rival Montgolfier, although neither the report nor the letters from Annonay had made mention of the kind of gas used by that experimenter to inflate his balloon. By one of the frequent coincidences in the history of the sciences, hydrogen gas had been discovered six years previously by the great English physician Cavendish, and it had hardly even been tested in the laboratories of the chemists when it all at once became famous. A young man well versed in physics, Professor Charles, assisted by two practical men, the brothers Robert, threw himself ardently into the investigation of the modes of inflating balloons with this gas, which was then called INFLAMMABLE AIR. Guessing that it was much lighter than that which Montgolfier had been obliged to make use of in his third-rate provincial town, Charles leagued himself with his two assistants to constrict a balloon of taffeta, twelve feet in diameter, covered with india-rubber, and to inflate it with hydrogen.