Today on the Google home page is a Doodle, aka special Google logo for the 90th anniversary of the first demonstration of television.
On January 26, 1926, John Logie Baird repeated the transmission for members of the Royal Institution and a reporter from The Times in his laboratory at 22 Frith Street in the Soho district of London. By this time, he had improved the scan rate to 12.5 pictures per second.
It was the first demonstration of a television system that could broadcast live moving images with tone graduation.
This is what the image looked like:
At bairdtelevision.com you can learn more about the history around this. Specifically at this page which shares the first demo. Here is video of it:
Pretty wild stuff.
Forum discussion at Google+.