"Exactly, sir," agreed Bob.  "That is, the electrical waves are projected into the air and disturb this air in a way to make it pulsate in the same manner as your voice makes the diaphragm pulsate.  These waves are then carried through the atmosphere in every direction, and sooner or later reach the antennae wires of some station equipped to receive them.  Down these wires they dash, are registered and magnified in the wonderfully delicate vacuum tube, and from it are carried up into the receivers at your ears."