This Day in Geek History: June 30

1879 The first electric company in the U.S. to produce and sell electricity California Electric Light Company is established in San Francisco, California . 1905 Albert Einstein publishes the article “ On the Electrodynamics of Moving Bodies “, wherein he introduces the concept of special relativity . 1908 At around 7:15am, northwest of Lake Baikal, Russia , a huge fireball nearly as bright as the Sun is seen crossing the sky. Minutes later, there is a huge flash and a shock wave felt up to 400 miles (650km) away. Over Tunguska, a meteorite traveling at over 60,000mph (25km per second) penetrates Earth’s atmosphere, heats to about 10,000°C, and detonates 3 to 4 miles (6 to 10km) above the ground. The blast releases the energy of 10-50 Megatons of TNT...