Weather 



127 



Dew and Frost 



it often condenses 

 other objects. This 

 there are no clouds 

 the drops of water 

 as they glistened in 

 the condensation of 

 had radiated their 



. When there is much water vapor in the air 

 and forms drops of water on foliage and 

 is dew. It is more apt to form on nights when 

 and no wind. You have undoubtedly noticed 

 on grass and other plants, or on spider webs, 

 the morning sunlight. They were formed by 

 vapor coming in contact with objects which 

 heat and become cooler than the air. In 



United States Weather Bureau. 



STRATUS CLOUDS 



Cloud layers that often veil the mountains. 



case the temperature of the air near the earth falls to the 

 freezing point, a coating of minute ice crystals forms in place of 

 dew. This is frost. Early frost is greatly feared by farmers, 

 since it destroys vegetation and prevents the ripening of 

 crops. 



Clouds. When water vapor condenses in the air near the 

 earth into small drops not heavy enough to fall, it is called 



