Fluorescent lamp began with the Geissler tube continued as even better vacuums were produced. The most famous was the evacuated tube used for scientific research by William Crookes. That tube was evacuated by the highly effective mercury vacuum pump created by Hermann Sprengel. Research conducted by Crookes and others ultimately led to the discovery of the electron in 1897 by J. J. Thomson and X-rays in 1895 by Wilhelm Roentgen. But the Crookes tube, as it came to be known, produced little light because the vacuum in it was too good and thus lacked the trace amounts of gas that are needed
The Amazing Race en Discovery Channel 2 route markers in this season were coloured blue and black, including the clue envelopes and the Pit Stop. None of the eliminated teams were present at the Finish Line. Applications were accepted from 13 December 2009 and finished on 8 February 2010. Semi-finalist interviews were held sometime in March 2010 and the final casting interviews took place around April 2010. According to Discovery's official website, the four official sponsors of the second season of "The Amazing Race en Discovery Channel" were Bridgestone, Samsung, Visa and Wii Party. The sponsors played a major role in the series by providing prizes and