The formal monotonous ticking of the Louis Quatorze clock annoyed him.
The sullen murmur of the bees shouldering their way through the long unmown grass, or circling with monotonous insistence round the black-crocketed spires of the early June hollyhocks, seemed to make the stillness more oppressive, and the dim roar of London was like the bourdon note of a distant organ.
The mere cadence of the sentences, the subtle monotony of their music, so full as it was of complex refrains and movements elaborately repeated, produced in the mind of the lad, as he passed from chapter to chapter, a form of revery, a malady of dreaming, that made him unconscious of the falling day and the creeping shadows.
…room, with a vermilion-and-gold ceiling and walls of olivegreen lacquer, he used to give curious concerts in which mad gypsies tore wild music from little zithers, or grave yellow-shawled Tunisians plucked at the strained strings of monstrous lutes, while grinning negroes beat monotonously upon copper drums, or turbaned Indians, crouching upon scarlet mats, blew through long pipes of reed or brass, and charmed, or feigned to charm, great hooded snakes and horrible horned adders.
There are no more uses of "monotonous" in the book.