A spinthariscope consists of a fluorescent screen, a magnifying eyepiece, and a speck of radium. By looking through the eyepiece, one sees scintillations caused by alpha particles from the radium hitting the screen. William Crookes, a prominent English chemist, designed the form in 1903, coined the term (deriving it from the Greek word for scintillation), and arranged for its manufacture. The inscription on this example reads “UNITED STATES RADIUM CORPS. / NEW YORK.”