However trifling this experiment may appear at first sight, it added a new fact to the science of aerostation. The material employed by the baron was lighter and better than paper. It was what is called gold-beaters’ skin. This skin is simply the interior lining of the large bowel of the ox. It is carefully prepared, is relieved of the fat, stringy and uneven parts, is dried, and is afterwards softened. Little balloons of this material came to be the fashion, and they are still frequently seen. At the same time, Montgolfier was busy constructing, at the request of the Academy of Sciences, a balloon seventy feet high and forty in diameter, with which it was proposed to repeat the experiment of Annonay. He took up his quarters in the magnificent gardens of his friend Reveillon, proprietor of the royal manufactory of stained paper in the Faubourg St. Antoine. The new balloon was of a very singular shape: the upper part represented a prism, twenty-four feet high the top was a pyramid of the same height; the lower part was a truncated cone, twenty feet in depth. It was made of packing-cloth, lined with good paper, both inside and out. The gossipping and prolix Faujas de Saint Fond thus describes this machine:--“It was painted blue, represented a sort of tent, and was richly ornamented with gold Its height was seventy feet; its weight 1,000 lbs.; the air which it displaced was 4,500 lbs. in volume, and the vapor with which it was filled was half the weight of ordinary air. The approach of the equinox having brought rain, all the conditions under which this balloon was constructed and exhibited were unfavourable. The structure was so large that it was impossible to get it together and stitch it, except in the open air--in the garden, in fact, where Montgolfier commenced its construction. It was a great labour to turn and fold this heavy covering, while the liability of the thick paper to crack was an additional difficulty. Not less than twenty men were required to move it, and they were obliged to use all their skill, and every precaution, not to destroy it. No balloon had ever given so much trouble. On the 11th of September the weather improved, and the balloon was entirely completed and prepared for the first experiment. In the evening the attempt was made. It was with admiration that the beholders saw the beautiful machine filling itself in the short space of nine minutes, swelling out on all sides and showing the full symmetry of its artistic form. It was firmly held in hand, or it would have risen to a great height. On the following day the actual ascent was to take place, and the commissioners of the Academy of Sciences were invited to be present. In the morning thick clouds covered the horizon, and a tempest was expected; but as there was an ardent desire that the ascent should take place without delay, and as all the gearing was in order, it was resolved to proceed.