340 J. Lawrence Smith on Meteorites. 
which becomes entangled in the atmosphere? If so, how great 
the wonder that the earth has never intercepted one of those 
spheres, and that all should have struck the stratum of air sur- 
roundiug our globe (some fifty miles in ene and escaped the 
body of the globe 8000 miles in diam It is said that the 
pos 6 has never intercepted one of siiese. on: ; for if we collect 
together all the known meteorites, in and out of cabinets, they 
would hardly cover the surface of a good sized room, and no one, 
of them could be looked upon as ia. ontel mass upon which 
‘we might suppose the others to have been grafted ; and this would 
appear equally true, if we consider the known meteorites as 
representing not more than a agnedecines part of those which 
have fallen. 
If it be conceived that the same body has given rise to them, 
and is still wending its path through space, only seeming by its 
repeated shocks with our atmosphere to acquire new vigor fora 
new encounter with that medium, the wonder will be greater, 
that it has not long since encountered the solid part of the globe ; 
but still more strange, that its velocity has not been long since 
destroyed by the resistance of the atmosphere, through which, it 
must have made repeated crossings of over 1000 miles in extent. 
But it may be said that facts are stronger than arguments, and 
that bodies of great dimensions (even over one mile in diameter) 
have been seen traversing the atmosphere, and have also been 
seen to project fragmeuts and pass on. Now of the few instances 
of the supposed large bodies, I will only analyze the value of the 
data upon which the Wilton and Weston meteorites were Cal- 
culated ; and they are selected, becanse the details connected with 
them ane more accessible. The calculations concerning the latter 
were made by Dr. Bowditch; but his able calculations were based 
on deceptive data,—and this is stated without hesitation knowing 
the difficulty admitted by all of making correct observation as to 
size of luminous bodies passing rapidly through the atmosphere. 
Experiments, that would be considered superfluous, have been in- 
stituted to prove the perfect fallacy. of making se but a most 
erroneous estimate of the size of luminous bodies, b y their appa- . 
rent size, even when their distance from the observer and the true 
size of the object are known ; how much more fallacious then, 
any estimate of size made, where the observer does not know the 
true size of the body, and not even his distance very accurately. 
In my experiments, three solid bodies in a state of vigorous 
incandescence were used ; Ist, charcoal 04 canvases electri- 
city ; 2nd, lime heated byt the oxy-hydrogen blowpipe ; 3d, steel 
in a state of incandescence in a/stream of poche gas. They 
of li observed on a clear night at different distances, a aie body 
of li . i washout bord ents Hel pyiaa wit 
