The flying island inhabited by scientific quacks, and visited by Gulliver in his “travels.” These dreamy philosophers were so absorbed in their speculations that they employed attendants called “flappers,” to flap them on the mouth and ears with a blown bladder when their attention was to be called off from “high things” to vulgar mundane matters. (Swift.)
“Realising in a manner the dreams of Lapnta and endeavouring to extract sunbeams from cucumbers.” —De Quincy.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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