2-20 Jccount of an Aerostatic Foj/agc. 



arran2;enient of an equal number of bars of the same sub- 

 stance in a box of brass. 



The effects of the al)ove compound magnets should then 

 be tried against others con\posed of bars of the three dif- 

 ferent substances, various in number and in the mode of 

 arrangement; and, lastlv, it would be interesting to make 

 a series of experiments on chemic;d compounds, formed by 

 uniting different proportions of carbon, sulphur, and phos- 

 phorus, with one and the same mass of iron. These qua- 

 druple compounds, which, according to the modern che- 

 mical nomenclature, may be called carburo-sulphuro-phos- 

 phurets, or phosphuro-sulphuro-carburets, 8cc. of iron, are 

 as yet unknown as to their chemical properties, and may 

 also, by the investigation of their magnetical properties, 

 afibrd some curious results. At any rate, an unexplored 

 field of extensive research appears to be opened, which pos- 

 sibly may furnish important additions to the history of mag- 

 netism, a branch of science which of late years has bceu 

 but little augmented, and which, amidst the present rapid 

 progress of human knowledge, remains immersed in con-i 

 siderabk'. obscurity. 



XXXVIII. ykcGunt of an Aeroslat'tc V(>yage performed li/ 

 ]\I. Guv-LussAC, oil. the S9//1 of Friutidor, Year 12; 

 and read in the National Institute, Fendemiaire Qth^ 

 Year 13*. 



X HE author, after giving an account of the instruments 

 he took with him for his obgervations, and the changes 

 which he introduced in them in consequence of the obser- 

 vations made during his first voyage, savs : All our instru- 

 ments being ready, the day of my departure was fixed for 

 the 39th of Fruolidor. I, indeed, ascended that day from 

 the Conservatoire dcs Arts ct Metiers, at 40 minutes past 

 nine, the barometer being at 76-525 centimetres, the hy-r. 

 gromcter at 57'5°, and the thermometer at 27-75°. M. Boii- 

 vard, who mal.es metearologicai observations every day at 

 the observatory of Paris, thought the atmosphere full of 

 vapours, but vi'ithout clouds. Scarcely had I risen a thou- 

 sand metres when I indeed saw a light vapour dispersed 

 throughout the whole atmosphere below me, and through 

 which I observed distant objects confusedly. 



• From the Journal cle PIj) ^iqnc, 



Wlieu 



