To show spectral lines of pure substances. Mercury and Helium tubes can be used as sources for experiments on the measurement of wave length of light. The gas pressure used results in well-defined emission spectra. These are glass tubes about 26cm long, central capillary portion about 9-10cm long with electrodes sealed at both ends and connected to lead wires protected by metal caps. Provided with loops welded to caps for electrical connection. Needs an induction coil 5cm spark, or a suitable transformer. Except for Neon and Helium, these can not be used as lamps. Length of capillary portion can be varied as required.
Note: The tubes are made of Soda Lime Glass.