Understanding the Weather [ 43 1 



become globules of cloudy ice. These globules may fall, on descend- 

 ing air currents, into warmer rain levels of air and take on a layer 

 of ice from contact with rising drops. Again the growing ice pellets 

 may be tossed far up, and again a layer of snowy ice will be added 

 to them. 



This up-and-down movement may continue until the ice pellets 

 have a dozen or more layers. Records show that hailstones having 

 twenty-five layers, and as big as baseballs, once fell at Annapolis, 

 Maryland! 



Thunder and Lightning 



Many children are frightened by thunder and lightning. Their 

 timidity usually fades in the course of time if they see that grown- 

 ups are undisturbed by storms, and if they can understand just 

 what takes place during a storm. This last, unfortunately, is easier 

 said than done. 



It is easy for a child to believe that there is such a thing as air 

 all about him, for he can often feel it blow. It is more difficult 

 for him to understand that electricity is always there as well. 

 Nevertheless, every bit of dust and droplet of moisture has its 

 charge a fact closely connected with lightning flashes. It may 

 be enough to explain to a young child that lightning is electricity 

 the same force that furnishes our modern lighting but on a grand 

 scale. Older children may be eager for more details. 



WHAT CAUSES LIGHTNING 



About the time a thunderstorm breaks, you may notice a 

 wind spring up as though from nowhere and blow toward the 

 storm. Scientists believe such currents of air may be part of a chain 

 of events somewhat on this order: As the wind blasts its way up- 

 ward, it cools and the vapor in it is changed to liquid form. The 

 speed of the rising current tears apart the drops of water that 

 form. The fine drops are carried to the top of the storm cloud 

 while the larger drops fall to lower levels. 



Now, it seems that the fine drops have a negative charge, while 

 the large drops are positively charged. When the electrical pres- 



