Crookes tube

A Crookes tube is an early type of vacuum tube that played a pivotal role in the development of modern electronics and our understanding of electricity and radiation. Invented by the British scientist William Crookes in the late 19th century, it consists of a sealed glass tube from which most of the air has been removed, creating a vacuum. The tube typically has two electrodes: a cathode (negative electrode) and an anode (positive electrode).