E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
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 Laputa, and endeavouring to extract sunbeams from cucumbers.De Quincy.