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velocity to be the same as that deduced from experiments 

 with artillery, the astronomer Schiaparelli has shown that if 

 a ball of 8 inches diameter and 32^ lbs. weight enter the 

 atmosphere with a velocity of 44§ miles a second, its 

 velocity on arriving at a point where the barometric pressure 

 is still only y^-th of that at the earth's surface will have 

 been already reduced to 3j miles a second. From this it 

 is clear that the speed of the meteorite after the whole of the 

 atmosphere has been traversed will be extremely small, and 

 comparable with that of an ordinary falling body. From 

 experiments lately made by Professor A. S. Herschel, it has 

 been calculated that the velocity of the meteorite which fell at 

 Middlesborough, in Yorkshire (359 R), on March 14, 1881, 

 was, on striking the ground, only 412 feet per second. 



Further, Schiaparelli points out that in the case supposed, 

 the energy already converted into heat would be sufficient to 

 raise 198,400 pounds of water from freezing point to boiling 

 point under the ordinary barometric pressure. The greater 

 part of this heat is, no doubt, carried off by the air through 

 which the meteorite passes; but still the wonder is, not that a 

 meteorite is small on reaching the earth's surface, but that , 

 any of it is left to ' tell the tale/ This sudden generation of 

 heat will cause a fusion and volatilisation of the surface-matter 

 of the meteorite, and in some cases a combustion of some of its 

 constituents : the products of this action sufficiently account 

 for the cloud from which a meteorite is generally seen to 

 emerge as also for the train often left behind. Owing to the 

 quick reduction of speed, the luminosity will be a feature of 

 the higher part of the course. The Orgueil meteorite of May 

 14, 1864 (296 Y), notwithstanding its easterly motion, was 

 seen over a space of country ranging from the Pyrenees to the 

 north of Paris, a distance of more than 300 miles. 



Next we may remark that the time of flight in the earth's 

 atmosphere will be very short, and reckoned only by seconds. 

 Even in the case where the matter is so good a conductor of 

 heat as iron, if we may judge from the time one end of a 

 poker may be held in the hand whilst the other end is in the 

 fire, the heat will not have had time to get far below the sur- 

 face before the body has reached the ground. In fact, even 



