Page:Jack Heaton, Wireless Operator (Collins, 1919).djvu/129

 he was able to detect the presence of electric waves up to distances of 500 feet.

A year later, of Russia, made a receiver for studying electric storms—lightning is only gigantic electric sparks—and this consisted of a coherer, a battery, a relay and an electric bell. Popoff connected one side of the coherer with a wire which he ran up into the air, or aerial wire as we call it now, and the other side of the coherer he grounded, as shown in the diagram. This was the first time that