96 B. V. Marsh on the Luminosity of Meteors. 
portion of their heat, which, as time is not afforded for it to pene 
trate the mass, m ust. be ex pended in burning off or vaporizing 
the surface layer of the stone. The greatest elevation of temper: 
ature must evidently take place in the remaining portions of the 
air, which, retaining nearly the whole of the heat developed in 
them, w ill reach a state of the most brilliant incandescence, the 
etendar of which will be vastly increased by the presence of 
the stony particles thrown off from the meteor. 
For pat gers I have assumed that the air is in all cases 
pressed to the density of that at the surface of the oath 
claim to accuracy. The ateuine attained must vary with the — 
n top way the most prion ‘brilliant perils must et a 
The nina kien to which these considerations toad is that the: 
upper regions of the atmosphere, even to its utmost limit, are 
O58 nd reservoirs of latent heat* most aoe eee for -” _ 
their i dates on arriving within bor denser regions of ee: ‘morpere &e. 
before them in consequence of ber enormous velocity, a aad by the relations of air i 
g ighly attenuated state to heat,” and he refers to hey Edinburgh Review, Jan 
1848, p.195. The in the Review is as follow é 
“ Arriving with planetary velocity at the confines of our a here, where the 
Ses teh thousand, perhaps ae times rarer than at the of the 
such a body would carry before it the air o on hick. My immediately uel om 
it to an enormous relative ext extent against wn surf ae 
a point as ti to weeane cna ga visi! 
pes task teow te Poieoun Sen ‘de Chim., xxiii, 341) that the latent heat 
‘given ht of air is greater, the lower the under which it exists. 
etd quantity Bla ed of air, besarte at those er’ contains. more at 
than the same quantity at the earth’s surface. 
‘oie than Soo ib tieited 
soon mpeg ‘with the immer Pinge seca tw ara ing 
