328 Intelligence and Miscellaneous Articles, 



bling a cannonade and the hissing of a cannon-hall through the air ; 

 some describe it as having been in a state of incandescence, while 

 others saw it dark and smoking. It penetrated into the ground to the 

 depth of less than a " braccio " (about 2£ Vienna feet), and was dug 

 out still hot, spreading a sulphurous smell, and covered with a crust. 

 Troili, although quite uncertain as to the nature of the phenomenon, 

 which he ascribes to a subterraneous commotion having thrown the 

 stone into the air, whence it fell again to the ground, was evidently 

 highly anxious to state its reality and every circumstance con- 

 cerning it. This, at a time when the scepticism about these phe- 

 nomena was such that anyone who asserted their reality could 

 only expect incredulity and even ridicule, gave a most meritorious 

 proof of moral courage. Supposing the Albareto meteorite to have 

 fallen to the ground in a nearly vertical direction, and to have come 

 from the west (as did the sounds preceding its fall), its point of de- 

 parture may be traced to the constellation of Leo, well known to be 

 the point from which the falling stars of the November epoch pro- 

 ceed. Its trajectory may have been a segment of the elliptical 

 orbit of a whole swarm of bodies moving within the sphere of terres- 

 trial attraction on the branch of a hyperbolic orbit through cosmical 

 space. Dr. Haidinger on this occasion recalled to mind his hypo- 

 thesis on the cause of the high temperature in meteoric masses — pass- 

 ing through the terrestrial atmosphere and generating heat by rapid 

 compression, in the same way as in Prof. Mallet's experiment, suc- 

 cessfully repeated before the Academy of Paris in 1803. Of late 

 years (1840-57) the experimental researches of Messrs. Bianconi, 

 Thomson, Joule, and Tyndall have shown that the temperature of a 

 thin string of water rapidly forced through a narrow spiral tube 

 rises from 1° F. to 4° F., that a solid body surrounded by a rapid 

 air-current was more heated than the ambient air, and that, if the 

 rapidity of the air-current be brought to 1780 feet in a second, this 

 difference of temperature may be raised to 137°. Even in an atmo- 

 sphere rarefied to the utmost limits, any solid progressing within it at 

 the rate of meteorites (6-30miles a second) would come to a far higher 

 temperature, still increased by the transformation of active forces 

 (light, electricity, magnetism, &c.) into heat, in consequence of the 

 resistance opposed to the rapid career of such a body. Prof. Bunsen, 

 in a note on the Meteoric Iron of Atacama (Leonhard and Bronn's 

 Jahrbuch, 1857, p. 265), calculated the loss of active force during 

 the fall of a solid coming into the terrestrial atmosphere with a pla- 

 netary celerity to be sufficient to heat it to 1,000,000° C. Supposing 

 mmhJ °f tn ^ s neat to De l° st m tne ambient medium, such a body 

 would still touch the ground wich a temperature of 2000° C. 



What Dr. Haidinger has done for meteorites, Prof. Tyndall has 

 ascertained for hailstones — the existence of a facial plane with inci- 

 pient fusion in consequence of the condensation of the air, and of a dor- 

 sal one, on which the rarefaction of the air has caused the congelation 

 of atmospheric water. Similar circumstances have been observed by 

 Prof. Goth, on hailstones fallen at Gratz in the summer of 1846 

 {Wiener Naturivissenschaftliche Abhandlungen, published by Haidin- 

 ger, vol. i. p. 91). — Imp. Acad. Sc. Vienna, March 27, 1864. 



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