E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Smells of the Lamp.
Said of a literary production manifestly laboured. Plutarch attributes the phrase to Pytheas the orator, who said, The orations of Demosthens smell of the lamp, alluding to the current tale that the great orator lived in an underground cave lighted by a lamp, that he might have no distraction to his severe study.