30 JANUARY 



west to east is proportionately less. The descending 

 atmospheric current retaining, in the region of less 

 circumference, the higher velocity it acquired in the 

 region of greater circumference, its eastward move- 

 ment outstrips that of the earth surface in the 

 temperate zones. Consequently, the atmosphere 

 over the British Isles has a constant, steady move- 

 ment from south-west to north-east, though this, of 

 course, is not always apparent, owing to local winds 

 arising from the presence or proximity of areas of 

 high or low pressure. 



The heated air, rising to very high levels, is cooled 

 down before it descends again to the earth surface ; 

 but in our latitude, coming in contact on its descent 

 with the warm ocean current known as the Gulf 

 Stream, and remaining in that contact while travel- 

 ling over the Atlantic, it regains a high temperature 

 from the water. This acquired heat is immediately 

 employed in sucking up moisture from the surface 

 of the ocean, which is borne along in the invisible 

 form of vapour. Our bodies are not sensible of heat 

 so employed, therefore in summer (that is, so long 

 as the atmosphere can use its heat in water-carrying) 

 we are conscious of a coolness at sea or on the west 

 coast. But in winter all is changed. The warm 



