1016 



Voltaic Electricity. Section 8: Electric Conduction in Gases. 



No. 63 052 



63 052. 1 : 6. 



63 055. 1 : 6. 



63 057. 1 : 4. 



63 058. 1 : 6. 



63 060. 



63 059. 1 : 5. 



63 061. 1 : 9. 



63 062. 



63.052. Geissler Tube, Figure, with uranium glass bulbs outside and stratified light in s. d. 

 the centre, 60 cm long 0. 9. 



63.053. -- idem, 100 cm long 0.15.0 



63.054. - - idem, 150 cm long 1. 5. 



63.055. Geissler Tube lighting up by friction, Figure, 50 cm long 0. 8. 



63.056. Geissler Tube, Figure, with mercury, lighting up by shaking, 35 cm long. . . 0. :.. u 



These tjibes are used in spiritualistic demonstrations for producing "spirit hands". 



63.057. Geissler Tube, Figure, with mercury salts, the colour changing when heated, 



35 cm long 0. 3. 



63.058. Holtz's Tube, Figure, 40 cm long, double 0. 10. 



The glow light passes in one direction only through the funicular apertures. The induction coil 

 used must work without closing current. 



63.059. Hittorff 's Tube, Figure, with base 0. 15. 



The current takes the longer path through the spiral-shape bent tube, since the discharge at 

 the points of the electrodes is prevented by the static electricity of the tube surrounding them. 



63.060. Absolute Vacuum Tube, Figure 0. li'. n 



63.061. Vacuum Scale after Cross, Figure, with stand and change-over switch, with tubes 



50 cm long 2. 4. 



The scale consists of six vacuum tubes evacuated to different degrees, viz., (1) luminous thu-ad 

 (de la Rive's apparatus); (2) luminous band; (3) stratified formation; (4) Geissler vacuum; (5) Tesla 

 vacuum; (6) Crookes's vacuum - - Rontgen vacuum. The change-over arrangement is double-pole 

 thus obviating any illumination of the tubes which are not connected up. 



Vacuum Bulbs with different degree of vacuum and differently illuminating types of glass: 



63.062. with luminous strips, with base, Figure 0. 6. (I 



63.063. with luminous band, with base 0. 6. 



63.064. with Geissler light, with base (I. 6. 



63.065. with white stratified light (CO 2 ), with base o. 7. 



63.066. with Tesla vacuum, with base. K i g u r e 0. 7. 



63.067. - with Crookes vacuum and green phosphorescent glass, with base 0. 8. 



f>X. 068. with Crookes vacuum and bluish-white phosplmi ex-cut glass, with base 0. 8. 



63,069. with Crookes vacuum and red phosphorescent glass (didyminm-oerinm gloss), with base .... 0. 10. 



63070. X-EayTube, for automatic evacution, with rubber tube attachemet, Figure . . 1. 0. 



For X-Ray Tubes for Practical Purposes: see p. 985. 



( I. li'.IOS. 6524, 6523, 2911, 2910, 2913. 

 211 1^.29 14,6506. 



