THE REASON WHY. 53 



"He givcth snow like wool: he soattereth the hoar frost like . ashes." 

 PSALM; CXLVII. 



proving the truthfulness of the Bible simile, which says, God 

 " giveth snow like wool." 



CRYSTALS OF SNOW, AS SEEN THROUGH A MICROSCOPE. FlG. 1. 



163. Why does it frequently feel warmer after a frost has 

 set in ? 



Because, in the act of congelation a great deal of heat is given 

 out, and taken up by the air, and thus the severity of the cold 



164. Why is it frequently colder when a thaw takes place ? 

 Because, in the process of thawing, a certain amount of heat is 



withdrawn from the air, and enters the thawed ice. 



165. What benefit results from these provisions of Nature ? 

 They moderate both the severity of frosts, and the rapidity 



of thaws, which, in changeable climates, would be seriously 

 detrimental to life, and to vegetation. 



166. Why are ftirs and woollens worn in the winter ? 

 Because, being non-conductors, they prevent the warmth of tho 



body from being taken up ly the cold air. 



167. Why are the skins of animals usually covered with 

 fur, hair, wool, or feathers ? 



