92 
THERMODYNAMIC METEOROLOGY 
Europe. From these minimum values the temperatures in 
the isothermal region increase about 10 degrees. These facts 
appear clearly in the Table 23, and the diagrams, where 
DottedXlne for Tropics 
Fig. 5 
the other data are presented. The data on Fig. 5 (P, —K, p, 
Qi — Qo) may be considered primary, and those on Fig. 6 
(Cp, Si — So, Wi — Wo, Ui — U 0 ) secondary, as being the 
machinery of the thermal engine. It is noted that (P,—K, p)