Experiments on Atmofpheric Air. 33 J 



gave almoft always a femi-tone lower ; hydrogen gas gave 

 nine or eleven tones higher -, the carbonic acid gas a third 

 lower; and the nitrous gas almoft the fame: a mixture of 

 oxygen gas and azotic gas, in the proportion of atmofpheric 

 air, gave again the tone of the laft mentioned air, that is to 

 fay, a femi-tone higher than each of the compound gafes 

 alone. As long as the two gafes were not uniformly mixed 

 there was a frightful difeord. Chladni has promifed to 

 publith a full account of thefe interefting experiments, 

 which 'differ entirely from thofe of Dr. Prieftley. 



EXPERIMENTS CN ATMOSPHERIC AIR. 



On the 14th inftant, at 7 o'clock in the evening, Cit. 

 Garnerin and Cit. Beauvais afcended in a balloon from the 

 garden d'Apollon, at Paris. At the height of nearly 403 

 toifes Cit. Garnerin let fall a cage, attached to a parachute, 

 and containing a cat, which fell very gently near the Port- 

 au-Bled. After 20 miriutes the balloon defcended at Nan- 

 teuil, diftant from Paris three leagues. At that place, Cit. 

 Beauvais, aide-de-camp to General Moulins, quitted Cit. 

 Garnerin, who departed at half pad three in the morning to 

 complete his aerial voyage, by taking a long flight. Cit. 

 Frederic Humboldt, a celebrated philofopher, had begged 

 Cit. Garnerin to fill with air a final! Safk with a ground 

 ftopper. Cit. Garnerin emptied the water which it con- 

 tained at the height of 669 toifes (1303 metres) above 

 Paris. Cit. Beauvais brought back the bottle, filled with 

 atmofpheric air, to Cit. Humboldt, who was defirous to knov? 

 if the carbonic acid gas afcends to fuch elevated regions. 



The obfervations of Saufiurc, made on the fummit of 

 Mount Blanc (at the height of 2.480 toifes), announced its 

 exiftence there •, but this philofopher was in an atmofphere 

 modified by the proximity of rocks. Cit. Humboldt found 

 in the air brought back by Cit. Beauvais, which had not 

 been under the like influence, between 8 and 10 milliemes 

 of carbonic air. Here then is a very heavy aeriform fluid 

 carried to the moft elevated regions of the atmofphere. 



Tht 



