tubes this way both ends of all the tubes can be melted and sealed therein the phosphor layer 18 is applied on the inner and outer surfaces of the tubes from the second tube 16 to the n u2212 1 th tube on the outer surface of the first tube 10 and also on the inner surface of the nth tube a pair of electrodes 28 on the cathode 26 is connected to terminals 42 on the base 40 at each end refer to fig2 fig1 the pair of stems 34 in fig2 is structured with a cathode 26 a pair of electrodes 28 and a cap 36 the cathode 26 is assembled in each of the two discharge chambers of the first tube 10 the outer diameter of the cap 36 is the same as that of the fifth tube 24 the cap 36 is attached to each end of the first tube 10 the second tube 16 the third tube 20 the fourth tube 22 and the fifth tube 24 heating at the points where the two caps 36 meet all of the discharge tubes can seal both ends of all the tubes with the isolator 12 the through holes 14 and the sealing of both ends of all the discharge tubes a succession of interconnected discharge chambers can be formed assemblies with more than 5 tubes can be formed with the method mentioned above let 39 s say the.