68 HISTORT OF AEROSTATION. 



was 26"'2 feet; and in the descent, a gust of wind having Mown the 

 machine over some large trees in an adjoining garden, M.Pilatre 

 suddenly extricated himself by throwing straw and wool on the fire, 

 which raised him at once to a sufficient height. On descending 

 again, he once more raised himself to a proper height by llio same 

 means. Some time after, he ascended, with M. Girond de Villette, 

 to the height of 33O feet; hovering over Paris at least nine minutes 

 in sight of all the inhabitants, and the machine keeping all the while. 

 a steady position. These experiments shewed, that the aerostatic 

 macliines might be raised or lowered at the pleasure of the person' 

 who ascended. On the 21st of November, 1783, therefore, M. 

 Pilatre, and the Marquis d'Arlandes, undertook un ai-rial vo\. 

 which lasted about 25 minutes, and during which time they passed 

 over a space of above five miles. From the account given by the 

 Marquis, they met with several different currents of air, the effect of 

 which was to give a very sensible shock to the machine, and the di- 

 rections of the motion seemed to be from the npper part downwards. 

 It appears also that they were in some danger of having the balloon 

 burnt altogether; as the Marquis observed several round holes 

 made by the fire in the lower part of it, which alarmed him consi- 

 derably, and, indeed, not without reason. However, the progress of 

 the fire was easily stopped by the application of a wet sponge, aud 

 all appearance of danger ceased. 



This vojagc of M. Pilatre, and the Marquis, may be said to con- 

 clude the history of aerostatic machines which are elevated by 

 means of fire; these having been soon after superseded by balloons, 

 in which inflammable air was enclosed. This gas being consider, 

 ably lighter than heated atmospheric air, possessed many advantages 

 over the other. The first experiment was made by two brothers, 

 Messrs. Robert and M. Charles, professors of experimental philo- 

 sophy. The bag was composed of lutestring, varnished over with 

 a solution of the elastic gum, called caoutchouc, and was about 

 thirteen Knclish feet in diameter. Many difficulties occurred in fill- 

 in" it with the inflammable air ; but being at la>t set at liberty, after 

 having been well filled, it was thirty-five pounds lighter than an 

 equal bulk of common air. It remained in the atmosphere only 

 three quarter* of an hour, during which it traversed fifteen miles. 

 Its sudden descent was supposed to have been owing to a rupture 

 tvhich had taken place when it ascended into the higher regions of 

 the atmosphere. The event oi this experiment; aud the aerial 



