Their light bulbs burned out after 150 hours, but Edison improved that to 400 hours by 1884, and 1,200 hours by 1886. Edison and Swan sued each other for violating each other's patents.

As the eclipse of 1878 approached, Edison created the tasimeter, an instrument to measure the sun’s heat. Edison would test the tasimeter in Wyoming, but it would be a failure.

Still life of the first electric light bulb, invented by Thomas Alva Edison in 1879 and patented on January 27, 1880. Welgos / Getty Images. By Jennifer Latson. October 21, 2014 10:30 AM EDT.

A set of rare light bulbs, including two created by Thomas Edison, just sold for $30,000 US at auction. Some of the bulbs were used in a lawsuit over the famous inventor's patent.