202 RADIATION. 



bad radiator) will not throw off the heat 

 of the boiling water from its surface. 



Q. Why is WATER KEPT COLD in summer- 

 time in a BRIGHT METAL pot, better than in an 



EARTHEN Vessel ? 



A. Because bright metal will not 

 absorb heat from the hot air, like an 

 earthen vessel ; in consequence of which, 

 the water is kept cooler. 



Q. Why are DINNER-COVERS made of BRIGHT 

 TIN or SILVER ? 



A. Light-coloured and highly-pol- 

 ished metal is a very bad radiator of 

 heat ; and, therefore, bright tin or silver 

 will not allow the heat of the cooked 

 food to escape through the cover by 

 radiation. 



Q. Why should a MEAT-COVER be very 

 brightly POLISHED ? 



A. If the cover be dull or scratched 

 it will absorb heat from the hot food 

 beneath it; and (instead of keeping it 

 hot) will make it cold. 



( Q. Why should a SILVER MEAT-COVER be 

 PLAIN, and not CHASED ? 



A. ff the cover be chased, it will 



