I seem to remember reading somewhere that Chambers mentioned Leng first in Maker of Moons. I would more associate its currency in Lovecraft with that and
Lang, Fritz. 1890-1976, Austrian film director, later in the U.S., most notable for his silent films, such as Metropolis (1926), M (1931), and The Testament of Dr. Mabuse (1932)
Andrew Lang, 1844 - 1912, author of
Adventures Among Books, Alfred Tennyson, Angling Sketches, The Arabian Nights, Aucassin and Nicolete, Ballads in Blue China, Ballads, Lyrics, and Poems of Old France, Ban and Arriere Ban, The Blue Fairy Book, The Book of Dreams and Ghosts, The Book of Romance, Books and Bookmen, The Brown Fairy Book, The Brown Fairy Book, The Clyde Mystery a Study in Forgeries and Folklore, Cock Lane and Common-Sense, A Collection of Ballads, The Crimson Fairy Book, Custom and Myth, Custom and Myth, The Death-Wake or Lunacy: a Necromaunt in Three Chimeras, The Disentanglers, Essays in Little, The Gold Of Fairnilee, Grass of Parnassus, The Green Fairy Book, The Grey Fairy Book, He, Helen of Troy, Historical Mysteries, Homer and His Age, The Homeric Hymns A New Prose Translation, How to Fail in Literature, The Iliad (as Translator), In the Wrong Paradise, Introduction to the Compleat Angler, James VI and the Gowrie Mystery, John Knox and the Reformation, Letters on Literature, Letters to Dead Authors, The Library, The Lilac Fairy Book, The Lock and Key Library The most interesting stories of all nations: Real life (as Contributor), Lost Leaders, The Making of Religion, The Mark Of Cain, Modern Mythology, A Monk of Fife, Much Darker Days, Myth Ritual and Religion Volume 1, New Collected Rhymes, The Nursery Rhyme Book, The Odyssey Done into English prose (as translator), Old Friends - Epistolary Parody, The Olive Fairy Book, On the Sublime (as contributor), The Orange Fairy Book, Oxford, Pickle the Spy Or the Incognito of Prince Charles, The Pink Fairy Book, Popular Tales (editor), Prince Prigio, Prince Prigio From "His Own Fairy Book", Prince Ricardo of Pantouflia being the adventures of Prince Prigio's son, The Puzzle of Dickens's Last Plot, Raleigh (editor), The Red Book of Heroes (editor), The Red Fairy Book, The Red Romance Book, The Red True Story Book (editor), Rhymes a la Mode, Robert F. Murray: His Poems with a Memoir, Shakespeare Bacon, and the Great Unknown, A Short History of Scotland, Sir Walter Scott and the Border Minstrelsy, Tales of Romance (editor), Tales of Troy and Greece, Tales of Troy: Ulysses the sacker of cities, 'That Very Mab', Theocritus Bion and Moschus Rendered into English Prose (editor), The True Story Book (editor), The Valet's tragedy and other studies, The Violet Fairy Book, The World's Desire, The Yellow Fairy Book, etc.