|Happy birthday Hans! (by sciencemug)|
[Hans Geiger's picture is adapted from a Public Domain image by sciencemug (source: wikia.com)]
Hans Geiger [pdf is here] is the "ilovephysics" guy who, in 1908, invents the first detector for ionizing radiation (you know the bastard right, it's the kinda radiation which shatters your chemical bonds giving you funny presents like cancer etc). Geiger's detector '1908 edition' is a counter for the alpha particles, namely just one of the existing forms of ionizing radiation. Hans dude makes it with future Nobel prize winner "ilovephysicsevenmore" Ernest Rutherford.
Later, in 1925, HG does it again (oops!) and, in collaboration with "ilovephysicstoobutdamniwon'tgetoneofthosefancysvedishprizesnono" Walter Muller, he perfects his device so that now it can sniff also beta particles and gamma rays (ie the other two, along with alpha particles, of the three most common types of ionizing skunks).
The XXth century world now has its "Geiger-Muller counter", a tool that is basically identical to the one the XXIth century world's still using.
Happy birthday, HG!