Spectra: A Book of Poetic Experiments was a small volume of poetry published in 1916 by American writers Witter Bynner, who wrote under the pseudonym "Emanuel Morgan", and Arthur Davison Ficke, who wrote as "Anne Knish." The book was intended as satire directed at the Imagism poetry movement.
From "Opus 6" by Emanuel Morgan:
Anne Knish's Opus 118:
Spectra was intended solely as a joke. Initially, even the publisher was fooled by the book, but he was let in on the joke before going to press. The authors assumed the ridiculousness of the work would shine through, but it was actually accepted as a legitimate poetic movement for two years. In 1918, Bynner admitted in a public speech that he had co-authored the book and explained the hoax.
Both Bynner and Ficke were accomplished poets of their time, but the Spectra poems are probably the most widely remembered of their work. Both authors admitted to the hoax having backfired to a certain extent, as it overshadowed their more serious work. Nonetheless, Ficke stated that he learned a good deal about composition while writing as Knish, adding that it actually influenced his later work.
Smith, William Jay. The Spectra Hoax. (Wesleyan University Press, Middletown, CT), 1961.