Geissler

He in rich, a German mechanician; born in Igelshieb, Germany, May 26, 1814. He became known as a maker ef physical and *hemical apparatus and principally as the inventor of Gei ler’s tubes, an apparatus for producing light by an lectrie discharge in vacuo. He died in Bonn, Pru ia, Jan. 24, 1879. Gei ler’s Tubes, tubes made of very hard gla , and containing -highly rarefied gases. Hach end of the tube has a platinum wire sealed into it to serve as electrodes. When a discharge of electricity is caused to take place in these tubes by i the elec- ‘rodes to the terminals of a Ruhmcorfi’s coil or a Holtz’s machine, very srilliant effects may be produced.