HISTORY OF AEROSTATION. 69 



voyage made by Messrs. Rosier and Arlandes, naturally suggested 

 the idea of undertaking something of the same kind with a balloon 

 /illed with inflammable air. The machine used on this occasion was 

 tbrnicd of gores of silk, covered with a varnish of caoutchouc, of a 

 spherical figure, and measuring 27i feet in diameter. A net was 

 spread over the upper hemisphere, and fastened to a hoop, which 

 passed round the middle of the balloon. To this a sort of car was 

 suspended a few feet below the lower part of the balloon ; and in 

 order to prevent the bursting of the machine, a valve was placed in 

 it ; by opening of whirh some of the inflammable air might be oc- 

 casionally let out. The car was of basket work, covered with linen, 

 and beautifully ornamented j being eight feet long, four broad, and 

 three and a half deep ; its weight 130 pounds. Great difficulties 

 again occurred in tilling the machine, but these at last being re- 

 moved, the two adventurers took their seats at three quarters after 

 one in the afternoon of the 1st of December, 1783. At the tim 

 the balloon rose, the thermometer stood at of Fahrenheit, and the 

 barometer at 30-18 inches; and, by means of the power of ascent 

 with which they left the ground, the balloon rose till the mercury 

 fell to 27 inches, from which they calculated their height to be 

 about 60O yards. Throwing out ballast occasionally as they found 

 the machine descending by the escape of some of the inflammable 

 air, they found it practicable to keep at pretty near the same dis- 

 tance from the earth, during rlie rest of their voyage j the quick- 

 silver fluctuating between 27 and 27*65 inches, and the thermo- 

 meter between 53 and 57, the whole time. They continued in 

 the air an hour and three quarters, and alighted at the distance of 

 twenty-seven miles from Paris ; having suffered no inconvenience 

 during their voyage, nor experienced any contrary currents of air, 

 as had been felt by Messrs. Pilatre and Arlandes. As the balloon 

 still retained a great quantity of inflammable gas, M. Charles de- 

 termined to take another voyage by himself. M. Robert accord- 

 ingly got out of the machine ; which now being 130 pounds lighter, 

 arose with such velocity, that in twenty minutes he was almost 900O 

 feet in the air, and entirely out of sight of terrestrial objects. The 

 globe, which had been rather flaccid, soon began to swell, and 

 the inflammable air escaped in great quantity. He also drew the 

 valve, to prevent the balloon from bursting ; and the inflammable 

 gas, being considerably warmer than the external air, diffused itself 

 all round, aud was felt like a warm atmosphere, lu teu minutes, 



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