ON THE GENERAL CIRCULATION OF THE ATMOSPHERE. 187 
the terrestrial current in the great system of atmospheric circulation 
embracing the whele earth. This circulation serves the purpose of dif- 
fusing upwards through the whole atmosphere the excessive heat of 
the torrid zone, of carrying this equatorial heat and humidity to mid- 
dle and high latitudes, and of bringing about the development of 
loeal air currents at those parallels. 
(8) The latter phenomena take place as a result of the production of 
alternating local increments and decrements of air pressure arising 
from the disturbance of neutral equilibrium in the higher strata of the 
atmosphere. 
(9) Areas of high and low pressure are consequences of the temper- 
ature and velocity of the air currents in the higher strata of the 
atmosphere. 
| consider the investigation of the causes and results of the disturb- 
ances of the neutral equilibrium of the atmosphere to be the most 
fundamental problem of meteorology, and the investigation of the 
geographical origin of the currents which pass over us on their way 
towards the pole to be the most important problem in’ weather predic- 
t.on. 
