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GENERAL SCIENCE 



is generally falling. Through the breaks in these clouds there 

 is almost always seen a high sheet of Cirro- or Alto-stratus. If the 

 mass of Nimbus is thrown up into small patches, or if low fragments 

 of clouds are floating much below the great Nimbus, they may be 

 called Fracto-nimbus or Scud. Light Scud clouds indicate wind. 



Clouds flying against the wind indicate rain. 



If clouds float at different heights and rates, but generally in opposite 

 directions, expect heavy rain. 



FIG. 16. Cirrus. 



Cirrus. About 5 to 7 miles high. Feather-like clouds high up 

 in the air Cirrus clouds are usually composed of ice particles. 

 They are often called Mare's Tail. 



If cirrus clouds dissolve and appear to vanish, it is an indication of fine 

 weather. 



The longer dry weather has lasted the less likely is rain to follow the appear- 

 ance of cirrus clouds. 



If cirrus clouds form in fine weather with a falling barometer, it is always 

 indicative of rain. 



When threads of cirrus clouds are brushed back from a westerly direction, 

 expect rain and wind. 



If the streaks of cirrus clouds point upward, they indicate rain. If down- 

 ward, they indicate wind and dry weather. 



Cirro-Stratus. 2 to 6 miles high. A fine whitish veil, some- 

 times quite diffuse, giving a whitish appearance to the sky, and 

 called by many, Cirrus Haze. Sometimes it shows more or less 



