"The departure of this Leviathan of the airy regions attracted immense crowds to the Champ de Mars yesterday afternoon. Considering that the avenues encircling that vast space were filled to suffocation, so that we found it extremely difficult to force our way to the open ground reserved for tickets, and that all the housetops were occupied by spectators, we think the number of persons present may fairly be stated at 80,000. Ample precautions had been taken to prevent disasters,--a strong police force, supported by a company of infantry and some cavalry, being present to maintain order. The balloon, which is 90 yards in circumference, and has consumed upwards of 20,000 yards of silk in its manufacture, was held down, while filling, by about 100 men, and the weight of at least 200 sandbags. The car was of wicker-work, comprising an inner surface of about 54 square feet divided into three compartments or small rooms, surmounted by an open terrace, to which the balloon was braced. Outside grapnels, wheels, and fowling-pieces, four of each, besides two speaking-trumpets, were lashed to the sides of the car. (The wheels were intended to be put to the car after alighting, in order to convey it back with horses.) The preliminary operations took considerable time, putting the patience of the spectators to a severe trial, a circumstance which perhaps prevented them from cheering when the words `_Lachez tout_!' were given, and the immense machine rose slowly and majestically into the air. We were rather surprised at the silence of the public, considering the very remarkable and interesting feat in aeronautics thus successfully performed. There were fifteen persons in the car, or rather cabin:--Monsieur Nadar, captain; Messieurs Marcel, Louis and Jules Godard, lieutenants; the Prince de Sayn-Wittgenstein, Count de Saint Martin, Monsieur Tournachon (Nadar's brother), Messieurs Eugene Delessert, Thirion, Piallat, Robert Mitchell, Gabriel Morris, Paul de Saint Victor, de Villemessant, and one lady, the Princess de la Tour d'Auvergne. The Princess was taking her usual drive to the Bois de Boulogne, when, observing an unusual movement in the neighbourhood of the Invalides, and having inquired the cause; she ordered her coach man to drive to the Champ de Mars. Having seen the balloon, she expressed a wish to make the ascent, and although Nadar had to the last moment refused to take any lady, and even his own wife, he could not resist the entreaty of the Princess. On starting, Monsieur Nadar climbed up the net-work and took off his hat to the spectators. The balloon took a north-easterly direction, and was visible for some time. At the moment of going to press, a communication has reached us, signed by the captain, Monsieur Nadar, and all those who had taken places in the balloon, stating that on alighting yesterday evening at nine o'clock at Ibarcy, near Meaux (Seine-et-Marne), three severe shocks