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 TubeA 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. Stand is marked with the institution in which it came. F.E. Becker & Co London. Stands 9.5 inches tall and 10.5 inches wide.