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Show MODERN THEORY OF THUNDER aaaBBMaaHaaaaa-a Intense Heat of Electrical Discharg Turns Vapor Into Steam and Causes Loud Explosion. There hsve been a great many different dif-ferent tbeorlea about the cause ol the noise we call thunder. Home savage nations think It Is caused by the clouds knocking together In a storm and making a spark, like two pieces of flint, with a crackling sound st the same time. Not long ago. when electricity first began to be under stood, many persons believed that th llgbtnjng made a bole In the air as It passed along and that tbe rush of air to fill up this vacuum caused the noise, just as It Is rsused by tbe air rushing back Into the vacuum In big cannon. The more modern theory, based on some remarkable experiments with very fluffy cotton thst was made dsmp Is that the Intense heat of'lbe electrical elec-trical discharge Inatantly turns tho surrounding vapor of the cloud Into aleam and causes sn explosion as fit-den fit-den and fierce as gunpowder. It la the number and diversity of thes explosions thst msk the crackling sound we hear when the thunder Ii close to us. which would not be th esse If tbe cause were the air rush Ing Into a single vacuum, as thai would make only one big bang. uat like a cannon. |