202 



OBSEEVATIONS ON THE WINDS. 



of these is commonly noticed to be nearly the same with that of the 

 cmrent on the earth's surface. In lieu oi cirro-stratus we see fleecy cumulus. 

 Shower-clouds are also common over this district. The atmosphere in 

 this part of the disturbance is in most cases clearer or more devoid of haze 

 than in the front, and temperature is also commonly lower ; but marked 

 exceptions occur to both these rules. A rapid and excessive decrease of 

 temperature is not uncommon when the wind has begun to veer, particu- 

 larly near the centre of the Cyclonic circulation. 



Let the reader now turn his attention to the other side of the centre's 

 path, and let him suppose the barometric minimum in its onward progress 

 to leave his station on the left of its course. Here the nimbus extends 

 over us, the wind after springing up commences to back, and continues to 

 do so throughout the passage of the disturbance. On this side we very 

 rarely experience the abrupt change from a rainy to a clear sky which is 

 BO usual on the right hand side. As the centre passes, the higher cloud 

 forms gradually degenerate into banks of dreary stratus, often attended 

 with an increase rather than any diminution of haze. As the rear of the 

 system approaches us on this side the bolder forms of cumulus are rarely 

 seen, and in place of the shower-clouds we commonly notice gloomy-looking 

 banks of condensed vapour in the middle and lower levels of the atmosphere, 

 while cirrus has usually almost or altogether disappeared. 



In the actual centre of a large depression the sky is often comparatively 

 clear. Shower-clouds are frequently visible, but these have usually here a 

 thin soft and disintegrated aspect, while cumulus tends to spread itself into 

 stratus, and cirrus lies in broken, though watery-looking patches. 



Distribution of Clouds and Weather in an Anti-Cyclonic Area. 



(132.) The above diagram shows the general distribution of clouds an^ 

 weather in a typical Anti-Cyclone, but the weather which characterizes 



