These tubes are straight and available in two sizes 20cm & 26cm in length. The electrodes
are placed in either side of the tube and connected with fine capillary tube in between. Available with (a) Helium,
(b) Neon,
(c) Ar, (d) Hydrogen, (e) Oxygen, (f) Nitrogen, (g) Iodine Vapours, (h) Alcohol vapours, (i) Carbon dioxide
(j) Carbon
Monoxide (k) Chlorine (l) Deuterium (m) Krypton (n) Sulphur (o) Xenon (p) Bromine etc. filled. Suitable
for the observation
of the typical spectrum of the gas filled in side the tube.
