J. Lawrence Smith on Meteorites. S31. 
the uppermost limit of the atmosphere, destroys their velocity 
and disperses the matter of which they are composed. Other 
grounds might be mentioned for supposing a difference between 
shooting stars and meteoric stones, and ave dwelt on it thus 
much because it is conceived of prime importance in pursuing 
the correct path that is to lead to the discovery (if it ean be made) 
of their origin. It is also of no small value to the beautiful and 
probable theory of shooting stars that we should separate every 
thing from it that may tend to affect its plausibility. 
Various theories have been devised to account for their origin. 
One is that they are small planetary bodies revolving around the 
sun, and that at times they become entangled in our atmosphere 
lose their orbital velocity by the resistance of the atmosphere and 
are finally attracted to the earth. They are also supposed to 
have been ejected from the volcanoes of the moon: and lastly 
they are considered as formed from particles floating in the at- 
mosphere. The exact nature of this last theory, is understood by 
reading the views of Prof. C. U. She , as € in an in- 
teresting report on meteorites published in 1848. The author* 
says—‘ The extra-terrestrial origin of meteoric stones and iron 
masses, seems likely to be more and more called in question with 
the advance of knowledge respecting such substances and as ad- 
ditions continue to be made to the connected sciences. Great 
electrical excitation is known to accompany volcanic eruptions, 
Which may reasonably be supposed to occasion some chemical 
changes in the volcanic ashes ejected ; these being wafted by the 
ascensional force of the eruption into the regions of the magneto- 
polar influence, raay there undergo a species of magnetic analy- 
* T must in justi Prof. | say that since his paper was written he has 
informisd ine thet he ao. Baty acta Se views; and I would now omit the 
criticism of them gid they not exist in his memoir uncontradicted and also were 
they not views stifPentertLined ly some. 
