A novel and important feature of this exhibition, however, was the substitution of living animals for sand-bags or other ballast, as used heretofore. In a wicker cage a cock, a duck, and a sheep were fastened, and these were carried some fifteen hundred feet into the air, descending uninjured, two miles from the starting-point, a few minutes later. The cage was broken open in the descent, but its occupants escaped injury, and the sheep was found quietly grazing when the rescue party arrived. The successful voyage of these caged animals stimulated the balloonists to attempt the crucial test of sending up a balloon carrying a human passenger. But from this perilous undertaking the boldest spirits recoiled, even the Montgolfiers refusing to venture. In those days, however, there was always a means of securing human beings, willing or otherwise, for any undertaking. Where gold would not tempt, it needed but a word of the monarch to commute the death-sentence of some criminal, placing him at the disposal of the scientists for a better or worse fate than the gallows, as the case might be. And so when Louis XVI heard of the plight of the balloon-makers, he came to their assistance with the offer of two condemned prisoners to be sent on the first aerial voyage. This offer had an unexpected effect. The pride of a certain high-minded aeronaut named Rozier, who had hitherto refused to risk his life, was touched at the thought of criminals performing an act that all honest men refused. "What! are vile criminals to have the glory of being the first to ascend into the air?" he exclaimed. "No, no, that must not be." And forthwith he offered his own services for the hazardous undertaking. The royal decree was accordingly repealed, to the chagrin of the criminals, no doubt, and preparations made for the momentous attempt. Montgolfier was engaged to construct a large balloon, and on the 15th of October, 1783, the trial was made in a garden in the Faubourg St. Antoine. Let no one suppose, however, that this first man-carrying balloon was cut loose from the earth and sent skyward to shift for itself, as might be gathered from the reluctance of persons to make the ascent. On the contrary, the balloon was held by strong cables, and allowed to rise only to a height of eighty feet--to the level of some of the lower windows of a modern sky-scraper--the aeronaut keeping it afloat for about five minutes by burning wool and straw in a grate made for the purpose.