190 THE EA.SOy 1VHY. 



' Come ye children, hearken unto me, I will teach you the fear of the Lord." 

 PSALM xxxv. 



Because the surfaces of the feathers fall upon the air obliquely, or 

 slantingly, and therefore, as the shuttlecock descends, it turns in 

 the air. 



Flit. 32. BATTLEDOEB AHD SHUTTLECOCK- 



837. Why do we hear a noise when we strike the shuttle- 

 cock with the lattledore ? 



Because the percussion of the shuttlecock upon the parchment of 

 the battledore causes it to vibrate, and the vibrations are imparted to 

 the air. 



838. Why is the sound a dull and short one ? 



Because the vibrations of the parchment are not very rapid, 

 therefore there is little intensity in the vibrations of the air. 



839. Why does the exercise, afforded by playing battle- 

 dore and shuttlecock, make us feel warm ? 



Because it makes us breathe more freely, and causes the blood to 

 flow faster ; we, therefore, inhale more oxygen, which produces 

 heat by combining with the carbon of our blood. 



840. Why does a Jcite rise in the air ? 



A kite rises in the air by the force of the wind, which sMIcct 

 obliquely upon its under surface. The string is attached to the 

 " belly-band " in such a manner that it is nearer the top than the 

 bottom of the band : this causes the bottom of the kite, when its 

 surface is met by ',he wind, to recede in the direction of the wind 



