illuminant

“They seemed to note the positions of the window at the one end and the door almost at the other, and even to take into account the single pendent electric light which up till then had been the sole illuminant.”

“For a good many years, beginning in London, Brighton & South Coast days, the station at Heathfield, between Tunbridge Wells and Eastbourne, was lighted by natural gas. The use of this illuminant was discontinued about 1934.”