This item was used at the Ballarat School of Mines Physics department until the 1970s-1980s to demonstrate that electrons have a straight line. A sealed conical glass tube, equipped with two electrical connections. One, at the narrow end, terminated inside with a sic shape electrode and faces a cross-shapped aluminium steel target near wide end. Other electrode is side branch, which also provided means of mounting on a polished wood circular stand. A Crookes Tube is an early experimental electrical discharge tube, with partial vacuum, invented by English physicist William Crookes and others around 1869-1875, in which cathode rays, streams of electrons, were discovered. May also be called a Crookes–Hittorf tube or Maltese Cross Tubemaltese cross, crookes tube, physics, electron emission demonstration, cathode rays, vacuum tube, electrons, crookes–hittorf tube, maltese cross tube