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LXIX. Intelligence and Miscellaneous Articles. 



AEROSTATION. 

 __^ Hamburgh, Aug. it. 



X ROFESSOR Robertson yesterday made his second ascent, 

 which, like the former, was exceedingly brilliant. At a 

 quarter past twelve he stepped into the car, with his friend 

 M. Lhoert, carrying with him barometers, thermometers, 

 a speaking trumpet, &c. At 35 mintutes after twelve, the 

 balloon being at the height of 600 toises, M. Robertson 

 launched a parachute, which fell veiy slowly. At three 

 quarters after twelve the balloon was at the height of about 

 1200 toises. During this ascent Mr. Robertson made several 

 new experiments, which had been suggested to him by some 

 of our philosophical men. 



Ang. I J. 



Professor Robertson and his friend returned hither at four 

 in the afternoon. Their second aerial voyage has been as 

 successful as the first. As the wind carried them towards 

 the sea, and the sky was so obscured by thick clouds that 

 they could not see to a great distance, they did not rise to 

 so great a height as the first time. The aeronauts descended 

 near the village of Rehout, in Holstein, having traversed 

 about eight miles in the course of an hour. Mr. Robertson, 

 during this voyage, made some new experiments, an account 

 of which he has promised to publish. 



Aui(. 14. 



By observation-*; made during his last ascent, iSIr. Robert- 

 son has found that barometric calculation docs not show 

 with precision the real heights in the atmosphere. He 

 weighed diflerent bodies by means of a spring balance, and 

 found a great difierence between their gravities in the de- 

 viated regions of the atmosphere compared with those at the 

 surface of the earth. He ascertained that the magnetic vir- 

 tue decreases as the square of tlie distances. He observed 

 that sounds may be conveyed upwards to the height of 200 

 toises, while downwards they can be conveyed only half 

 that distance. The solar rays collected in the focus of a lens 

 lose one-third of their intensity. Mr. Robertson is prepar- 

 ing to continue his tour to Petersburgh. 



Aug. 15. 



It was 42 minutes past twelve when Mr. Robertson de- 

 tached his balloon from the earth when he made his last 

 ascent. The barometer being at 21 inches 12 lines, and the 



thermometer 



