) 



46 Mechanical Philosophy. 



Observing the natural ascent of smoke and clouds 

 in the atmosphere, those artists were led to sup^ 

 pose that heated air, if enclosed in a suitable co- 

 vering, would also prove bouyant. Accordingly, 

 after several smaller experiments, by which this 

 idea was fully confirmed, they inflated a large bal- 

 loon with rarefied air, on the 5th of June, 1783, 

 which immediately and rapidly rose to the height 

 of six thousand feet, and answered their most san- 

 guine expectations. It was soon found that ma- 

 chines of this kind might be so contrived as to 

 convey small animals, and even human beings, 

 through the air with ease. The first human adven- 

 turer in this aerial navigation was M. Pilatre De 

 RoziER, a daring Frenchman, who rose in a large 

 balloon, from a garden in the city of Paris, on the 

 15th of October, 1783, and remained a consider- 

 able time suspended in the air. He made several 

 serial voyages of greater -extent afterwards, and in 

 two of them was attended by other persons. In a 

 short time, however, the use of rarefied air in 

 aerostation was, for the most part, laid aside, as 

 inconvenient and unsafe, and recurring once more 

 to the discovery of Mr. Cavendish, the philoso- 

 phers of Paris concluded that a balloon, inflated 

 with inflammable air, would answer all the pur- 

 poses of that contrived by the AIontgolfiers, 

 and would also possess several additional advant- 

 ages. They made their first experiment on the 

 23d of August, 1783, which was attended with 

 complete success; and the first human beings who 

 ventured to ascend in a balloon raised upon this 

 plan, were Messrs. Charles and Roberts, who 

 rose from Paris, on the 1st day of December in 

 the same year. The inflammable air balloons have 

 been generally used since that time; many serial 

 voyages have been performed in Europe and Ame- 

 rica; and what is remarkable, out of all the numer- 



