332 J. Lawrence Smith on Meteorites. 
“ Any great disturbance of the forces maintaining these clouds 
of meteor-dust, like that produced by a magnetic storm, might 
lead to the precipitation of portions of the matter thus suspended. 
If the disturbance was confined to the magnetic dust, iron masses 
would fall; if to the diamagnetic dust, a non-ferraginous stone ; 
if it should extend to both classes simultaneously, a blending of 
the two characters would ensue in the precipitate, and a rain 0 
ordinary meteoric stones would take place. 
“The occasional raining of meteorites might therefore on such 
a theory, be as much expected, as the ordinary deposition of mois- 
ture from the atmosphere. The former would originate in a me- 
chanical elevation of volcanic ashes and in matter swept into the 
air by tornadoes, the latter from simple evaporation. In the one 
case, the matter is upheld by magneto-electrie force ; in the other, 
by the law of diffusion which regulates the blending of vapors 
and gases, and by temperature. A precipitation of metallic and 
earthy matter would happen on any reduction of the magnetic 
tension ; one of rain, hail or snow, ona fall of temperature. ‘The 
materials of both originate in our earth. In the one instance 
they are elevated but to a short distance from its surface, while in 
the other, they appear to penetrate beyond its farthest limits, and 
possibly to enter the inter-planetary space ; in both cases, how- 
ever, they are destined, through the operation of invariable laws, 
to return to their original repository.” 
This theory, coming’as it does from one who is justly en- 
titled to high consideration, from the fact of the special atten- 
tion he has given to the subject of meteorites, may mislead, 
and for that reason objections will be advanced which will doubt- 
less entirely set aside this notion of terrestrial origin, and to this 
end [ would consider two fundamental principles of it. First of 
all it must be proved that terrestrial voleanoes contain all the va- 
rieties of matter found in the composition of meteoric bodies ; 
there is no doubt that many of the varieties are ejected from vol- 
canoes, as olivine, &c., but then the principal one, nickeliferous 
iron has never in a single instance been found in the lava or other 
matter coming from volcanoes although frequently sought for. 
But the physical obstacles are a still more insuperable difficulty 
in the way of adopting this theory. In the first place it is con- 
sidered a physical impossibility for tornadoes or other currents of 
air to waft matter, however impalpable, “beyond the farthest lim- 
its of the earth and possibly into interplanetary space.” Again 
cause th 
