Fluorescent lamp began with the Geissler tube continued as even better vacuums were produced. The most famous was the evacuated tube used for scientific research by William Crookes. That tube was evacuated by the highly effective mercury vacuum pump created by Hermann Sprengel. Research conducted by Crookes and others ultimately led to the discovery of the electron in 1897 by J. J. Thomson and X-rays in 1895 by Wilhelm Roentgen. But the Crookes tube, as it came to be known, produced little light because the vacuum in it was too good and thus lacked the trace amounts of gas that are needed
Wilhelm Olivier Leube Wilhelm Olivier Leube Wilhelm Olivier Leube (14 September 1842 – 16 May 1922) was a German internist born in Ulm. He studied medicine in Tübingen, Zurich, Berlin and Munich, and from 1868 worked as an assistant at the medical clinic in Erlangen. In 1872, at the University of Jena, he became a professor of pathology and special therapy, as well as director of the medical clinic. At Jena, one of his assistants was noted physician Ottomar Rosenbach (1851–1907). Afterwards he was a professor at the Universities of Erlangen (1874–1885) and Würzburg, where in 1895/96 he served as university rector. Wilhelm