(1) A small Geissler tube (No. 1) was lighted up by the small coil. The capillary part showed a very bright, slightly rosy-tinted stream. Negative bulb was filled with rosy-purple light, the violet-pole glow being confined to the extent of the electrode. Positive bulb of the same rosy-purple colour, but stream slightly contracted in volume. Glow throughout quiescent, and no stratification in the tube. A compound-prism spectroscope, taking in the whole of the spectrum, showed in the capillary stream, from yellow to red, a fairly bright wedge, having a dark band in the centre, and six bright columns, with dark lines at intervals, shading off on either side. On the more refrangible side of the yellow, the spectrum was composed of a set of bright bands and lines in the green, blue, and purple, one line only (in the green) standing out very bright. In the yellow and red no bright line stood out alone. The positive bulb gave a fainter spectrum of the same character, mainly confined to the centre, the violet, yellow, and red not being well seen. When the violet-pole glow was examined, the general character of the spectrum was quite changed: a brilliant broad band in the violet, a bright narrower one in the blue, and two bright lines in the green, with intermediate fainter lines throughout, were the main features. The yellow and red part of the spectrum was also changed. The yellow was fairly and evenly distinct up to the dark band; then came a somewhat brighter orange band, and after that the red, but rather obscure and cut off. No absolutely bright line could be traced in the red. [Sidenote: Nitrogen-tube No. 2. Glow described. Difference of spectra of capillary stream and violet-pole glow. Junction of the violet-pole glow and capillary stream.] (2) To compare the capillary stream and the violet-glow, a second nitrogen-tube (No. 2) was used. This tube was larger in bulk and bore than No. 1. The glow in the bulbs was considerably fainter and more salmon-coloured; and there was much stratification in both, extending to the capillary bore. (This stratification was considered due to H, as the three principal lines of that gas came out very brightly in the spectrum.) The difference of the spectra of the capillary stream and of the violet-pole glow was extremely well marked—the former consisting of a set of bright lines and bands of fairly uniform intensity, while the latter was split up into a few bright bands with fainter lines between. The yellow and red of the violet-glow were very weak as compared with the same region of the capillary spectrum. No bright line appeared in the red. The tube being properly adjusted for the purpose, the junction of the violet-pole glow and the capillary red-glow was easily observed. The bright bands of the violet-pole were seen to run into the capillary line-spectrum, and then, gradually getting finer and more pointed, to fade out.