helium, He, atomic_number_2
Meaning: a very light colorless element that is one of the six inert gasses; the most difficult gas to liquefy; occurs in economically extractable amounts in certain natural gases (as those found in Texas and Kansas)
But what assurance was there that the other was Carthoris of Helium?
The day following the coming of Vas Kor to the palace of the Prince of Helium great excitement reigned throughout the twin cities, reaching its climax in the palace of Carthoris.
In the council chamber of John Carter, Warlord of Mars, was Tardos Mors, Jeddak of Helium; Mors Kajak, his son, Jed of Lesser Helium; Carthoris, and a score of the great nobles of the empire.
Bear with you the authority of the Warlord of Barsoom, and of the Jeddak of Helium to offer every resource of the allied powers to assist Thuvan Dihn to recover his daughter and punish her abductors, whomsoever they may be.
Either of them, when seen in projection against the brilliant solar disk, appears white, not red, as against a background of sky. The quiescent prominences, whose elevation is often from forty thousand to sixty thousand miles, consist, as the spectroscope shows, mainly of hydrogen and helium.
With a word of farewell he touched the button which controlled the repulsive rays, and as the flier rose lightly into the air, the engine purred in answer to the touch of his finger upon a second button, the propellers whirred as his hand drew back the speed lever, and Carthoris, Prince of Helium, was off into the gorgeous Martian night beneath the hurtling moons and the million stars.