THE THERMODYNAMIC TERMS 
375 
primary maximum, 9,806 at 50,000 meters, in this computation. 
[Wi — Wo) and (Ui — Uq) pass through entirely similar changes 
above 38,000 meters, and they all correspond to the very rapid 
increase in the temperature of the gases of the upper absorption 
level. It is evident that the pyrheliometer measures the trans 
mission and the minor absorption up to about 38,000 meters, 
but is not cognizant of the great absorption area above it where 
the absorption is nearly complete. The bolometer measures the 
relative ordinates of the true solar spectrum, unless some of 
them are absorbed, but for its total energy depends upon the 
computations and integrations of the spectrum curve at given 
temperatures. This is shown by the spectrum to have lost 
nearly half the incoming energy in the short waves having long 
ordinates, these corresponding with the upper absorption 
region, besides some minor absorptions attributed to aqueous 
vapor selective absorption bands belonging to the lower region. 
The general slope of the (T\ — E 0 ) line indicates that the 
equal terrestrial radiation is required to balance the solar radi 
ation, generally large below but small above, in accordance 
with the prevailing temperatures and the equation of equilib 
rium, as will be explained. 
The corresponding values of K w , log c, a, in K w = c T a , 
have been computed. The exponent a = 3.819 at the surface 
gradually falls to a minimum 3.564 at 38,000 meters; it rises 
to a maximum 3.905 at 45,000 meters, then falls to about 3,600 
at the vanishing plane. Further computations will be under 
taken in respect to the region above 38,000 meters. (Fig. 79.) 
The Constituents of the Solar and the Terrestrial Radiations in 
the Earth’s Atmosphere 
It will be convenient to transform the thermal data which 
have been computed in the (Meter, Kilogram-second) (M. K. S.) 
system into the corresponding values in the (Centimeter-gram- 
second) (C. G. S.) system, before proceeding to a further 
discussion of the transmitted and absorbed constituents of the 
solar and the terrestrial radiations. The term (Qi — Qo) in