94 B. V. Marsh on the Luminosity of Meteors, 
Whence it appears that 
1 vol. of air at 32°, by having its temperature raised 491° becomes 2 vols, 
] “ sc “ “ a “a “ 982 “ce 3 uw 
P ead “ at 4“ iT “ “« 41473 “ 4 & 
&c.,—the increase being 1 volume for each 491°. 
But it has already been shown that. y Of the heat employed in 
this process, about 2 (more exactly 5°29.) is B egibe by the air 
and rendered latent. Hence, of each 491° expended as above 
ita” or about 144°, are rendered latent. Tt therefore follows 
t of 
Vol Latent heat, 
rte ‘at "32° by having its temp. raised se becomes - vols. and beset nese: pe ; 
7 oe me «cc “ sc ue “ : & te 439 
and so on indefinitely. 
Now, inasmuch as it is known that at the height of 3°43 miles 
the volume of a given weight of air is twice what it is at the 
earth’s surface, and that as we ascend the number of volumes is _ 
eeables) for each addition of 3°48 miles to the height, the 
Bore poomesonalione enable us to calculate the amount of Toon 
any given weight or bulk of air at any given height 
within | the limits of the atmosphere. 
Latent Number of grt 
f degrees of latent | heat in | jof air in 
heat. volume tojl mile 
near 
bs a Seep & } c 1 W, h ' 
— S 
n being — num-|SUtface 
ber terms of this gree. |Weight 
pay ==3'43. 144 Q"-1 
a being —3-43. 2 - 
—— Qn, \ ‘a 1a(=) 
eS se a ee 
Sree es es 
eM SNe male, ake Poay he ee ee cea 
a ae oe pe ar aay, eee 
