DEW. 203 



absorb the heat of the food covered by 

 it; and instead of keeping it hot, will 

 make it cold by absorption. 



Q. What is DEW ? 



A. Dew is the vapour of the air 

 condensed, by coming in contact with 

 bodies colder than itself. 



Q. Why is the GBOUND sometimes COVERED 

 with DEW ? 



A. The earth is more heated by solar 

 rays than the air, during the day ; but 

 at night, the earth parts with more heat 

 than the air, and becomes (in conse- 

 quence) 5 or 10 degrees colder. 



Q. How does the EAKTH "being COLDER than 

 the AIR account for the deposition O/"DEW? 



A. As soon as the air touches the 

 cold earth, its warm vapour is chilled, 

 and condensed into dew. 



Q. Why is the surface of the GROUND 

 COLDEB in a FINE clear NIGHT, than in a CLOUDY 

 one ? 



A. On a fine clear star-light night, 

 heat radiates from the earth Jreely, and 

 is lost in open space : but on a cloudy 

 night, the clouds arrest the process of 

 radiation. 



