Phenomena attending the Fall of Meteorites on the Earth. 349 



If we calculate, then, from the three last experiments the 



atomic weight of caesium, we have — 



12331 



123-31 



123-44 



Mean . . 123-35 

 As many of the salts of rubidium and csesium are isomorphous 

 with potassium-salts, the number 123-35 cannot be regarded as 

 a multiple or submultiple of the atomic weight of csesium. 

 Hence we draw the remarkable conclusion, that the new metal 

 possesses the largest atomic weight of all the known elementary- 

 bodies with the exceptions of gold and iodine. 

 [To be continued.] 



XLIII. Considerations on the Phenomena attending the Fall of 

 Meteorites on the Earth. — Part I. By W. Haidinger, 

 For. Mem. R.S. L. §■ E., and Director-General of the School 

 of Mines in Austria *. 



THE only falls of meteorites which I propose to take into 

 consideration in this paper, are those which have been 

 observed as accurately as possible. Generally in such cases 

 dates and particulars that can be perfectly relied upon are not 

 common. The phenomena taking place without warning and 

 occupying so short a period of time, it is only from persons 

 accustomed to receive impressions promptly that we can obtain 

 trustworthy observations. Dr. Gustavus Scheffczik, whilst on a 

 hunting-excursion, saw near Strakowitz in Bohemia, on the 

 29th of November, 1859, at 10 h 45' a.m., a luminous star-like 

 point appearing suddenly on a clear sky, due north 15° zenith- 

 distance, increasing gradually to an intensely luminous globe, 

 equal in size to one-third of the full moon (about one-third of 

 her diameter), and passing along a parabolic path towards 

 S. 60° E. When under an angle of altitude of 25° (azimuth 

 = 65°) it assumed an oval shape, the pointed end bent down- 

 wards and forwards, and lastly, apparently dissolved into many 

 large sparks, one of which evidently fell down in a vertical direc- 

 tion. Dr. Scheffczik estimates the phenomenon to have lasted 

 from four to five seconds. A noise as if myriads of birds were 

 flying through the air attracted his attention. According to his 

 watch, lj minute passed in silence after the disappearance of 

 the luminous appearances; then followed, quickly after each 

 other, four detonations (the last the most intense), resembling the 

 * A translation by Count Marshall, of a paper read before the Imperial 

 Academy of Sciences at Vienna, on the 14th of March, 1861. Commu- 

 nicated and revised by R. P. Greg, F.G.S. 



