RAIN THUXDER-STORMS. 31 



Rainy, when the fall of some drops and the appearance of the 

 weather is such as to indicate the approach of rain. 



Continued rain. 



Interrupted rain. 



Shower, which lasts not more than a quarter of an hour. 



General rain, which prevails over the whole extent of the 

 horizon. 



Partial rain, which falls from the clouds that pass over only a 

 small extent of country. 



The force of the rain may be indicated by the following 

 gradations : 



Drizzling rain, which falls in very small drops, almost like 

 those of mist. 



Slight or fine rain. 



Moderate rain. 



Heavy rain, 



Violent rain, heavy and strong pelting rain. 



The size of the drops seems to depend chiefly upon the height 

 of the clouds, and consequently upon the seasons and the cir- 

 cumstances of the temperature. 



The snow. The period of the first and last snow, the size of 

 the flakes, their forms. 



Sleet, which consists in small balls of snow, white and opaque, 

 commonly without a crust of ice, like the opaque nucleus found 

 within hail-stones, falling more frequently in spring and ia 

 autumn. 



Frozen rain drops should be distinguished from the preceding, 

 forms ; they make little balls of transparent ice. 



Hail. Indicate the size, form arid average weight of the 

 hail-stones. The number of different strata observed in the 

 larger stones. Whether any of them contain particles of sand 

 or any other foreign matter. The extent and course of the phe- 

 nomenon. 



THUNDER-STORMS. 



The time of beginning and ending of the storm must be indi- 

 cated as exactly as possible ; the point of the horizon whence it 

 rises, the direction of the clouds, of the wind and its variations, 

 and, if possible, the quantity of rain before and during the storm ; 



3 



