Although the author purports in the introduction to offer a balanced view of slavery, the novel in essence constitutes a paternalist apology for the practice (which was abolished in the colonies five years after the book was published). The larger part of the novel comprises vignettes about the day-to-day lives of the slaves and the colonists, as well as long discursive sections on the arguments for and against slavery, which are expressed either in the narrator's voice or through dialogues between Marly (the protagonist) and his fellow slave-drivers. It also features a sub-plot involving the attempt of the hero to reclaim the inheritance of his grandfather, who had once settled in Jamaica, and to marry the daughter of the man who had wrongly claimed that inheritance.
While the novel expresses some sympathy for the slaves who suffer under especially tyrannical overseers, it is deeply marked with racial hatred, not only towards Black people but also towards Jewish people. The narrator's comments on p.254 are characteristic: '[those who have] through the motives of humanity, taken the side of the blacks [...] are not aware, it is to be presumed, of their real character, otherwise they would never have once thought that it could be expedient with safety to loosen their bondage.'

The novel features much representation of the creole speech of the slaves. In the main, this is limited to brief one or two-sentence utterances (that are often repeated). A notable exception to this occurs on pages 135-138, when a slave named Tom Paine narrates, uninterruptedly, what might be described as a slave-centric version of Genesis and Exodus in dialect. The name of this character might be intended to associate him with demagoguery.
There is also an interesting passage in p.209 in which Marly dances with a creole partner, who involuntarily commits a 'lapsus linguae' which reveals her 'island education'. In addition to this, the novel features a brief sentence of Scots representation on p.299 and a section in the first chapter where Marly is refused a job because he cannot speak Gaelic (p.8).

Unexpectedly nondialectal characters: Marly is a native of Scotland and speaks Standard English in all but one occasion, when he speaks 'Scotch dialect' to a slave. In context, it is part of a comical section in which a slave is baffled first by his excessively grandiloquent overseer and then by Marly, when he asks him to translate the former.