jan 1, 1861 - William Crookes
Description:
London, United Kingdom1861
William Crookes discovered the element known as thallium in 1861. In 1917, he discovered protactinium. He also discovered the Crookes Radiometer in the late 1800’s(No specific date). The crookes radiometer is rarely used as an instrument. It was found to be insensitive and not easily calibrated. However, it helped contribute to science by paving the way for the more exact instruments in use today.
Added to timeline:
Date:
jan 1, 1861
Now
~ 165 years ago