138 SCIENCE OF COMMON THINGS. 



Heat in all bodies. What is latent heat? Heat in ice. 



8*77* Was there heat in Hie cold water and lime before they were mixed 

 together f 



Yes. All bodies contain heat. 



878 Is there heat even in icef 



Yes ; but it is latent (i.e. not perceptible to our 

 senses). 



Latent, from the Latin word lateo (to lie hid). 

 87*9 Does cold iron contain heat ? 



Yes ; everything contains heat ; but when a thing 

 feels cold, its heat is latent. 



88O What is meant by latent heat ? 



Heat not perceptible to our feelings. "When anything 

 contains heat without feeling the hotter for it, that heat 

 is called u latent heat. 



S81 Does cold iron contain latent heat f 



Yes ; and when a blacksmith compresses the particles 

 of iron by his hammer, he brings out latent heat ; and 

 this makes the iron red hot. 



382 Why is the air in the spring, when the ice and snow are melting, 

 always very chilly and cold 1 



Solid bodies, in passing to the liquid state, absorb heat 

 in large quantities ; when ice and snow are thawing, 

 they absorb heat from the air, in consequence of which 

 its temperature is greatly reduced. 



883 Why does the weather always moderate on the fall of snow t 



Bodies, in passing from the liquid to the solid state, 

 give out heat y snow is frozen water, and in its forma- 

 tion heat is imparted to the atmosphere, and its tem- 

 perature increased. 



884 Why does the temperature of melting ice and snow never exceed 

 32? 



Because all the heat imparted to melting ice and 

 snow becomes insensible, until the liquefaction is com- 

 plete. 



885 Can we be made to feel the heat of ice or snow f 



Yes. Into a pint of snow put half as much salt ; 

 then plunge your hands into the liquid ; and it will feel 

 so intensely cold that the snow itself will seem warm in 

 comparison to it. 



