The Astrophysical journal . in shape andfrom 3 to 6 cm in diameter. The cathode was arranged as fol-lows (see Fig. 2). A strip of sheet aluminium, 1 or 2 cm wide, wasbent into a cylinder which would just fit into the vacuum one end of this cylinder was riveted a circular aluminiumdisk which was perforated as densely as possible with holes of h, to1 mm in diameter. At the other end of the cylinder a platinumwire was attached, as shown in Fig. 2, and then passed through theside of the tube, where it served as one electrode. For anode wasused an aluminium disk completely filling the c
The Astrophysical journal . in shape andfrom 3 to 6 cm in diameter. The cathode was arranged as fol-lows (see Fig. 2). A strip of sheet aluminium, 1 or 2 cm wide, wasbent into a cylinder which would just fit into the vacuum one end of this cylinder was riveted a circular aluminiumdisk which was perforated as densely as possible with holes of h, to1 mm in diameter. At the other end of the cylinder a platinumwire was attached, as shown in Fig. 2, and then passed through theside of the tube, where it served as one electrode. For anode wasused an aluminium disk completely filling the cross-section ofthe tube. It was not permissible to make the anode small or to placeit in a side tube; for if the cathode rays, instead of falling uponthe metallic anode, struck the end of the tube, the glass became sohot that the atmospheric pressure was sufficient to crush it. Withheavier currents, especially in case the induction coil was used,the aluminium anode, like the anti-cathode in Rontgen bulbs, 26 J. STARK Rohre/. Ol-Pmnpe. 3 Ok Q~->Ggfi&eAoZ&y was so highly heated that it disintegrated (zerstaubte) faster than the cathode. The distance be-tween anode andcathode was alwayschosen so large thatthe Crookes darkspace did not reachthe anode; for if thiswere not the case,then the current wouldcease altogether or thedischarge become ir-regular. Accordinglythis distance was always greater than 10 cm and generally amounted to 25 cm. In the observations on the Doppler effect with mercury lines it reached 40 cm. That portion of the vacuum tube which lay behind the cathode and into which the canal rays passed varied in length, according to circumstances, between 4 and 20 cm. I. GasbdhaLurFig. 1 Twfhoden&tr Kanalstr. Fig. 2 As is well known, the cathode-drop increases as the gas-pressurediminishes, and simultaneously the length of the Crookes dark spaceincreases; this length may therefore serve as a rough measure ofthe cathode-drop. This method was employed in the case of thei
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectspectru, bookyear1895
