At the heart of this wide-ranging narrative is the story of the seafaring adventures of the eponymous hero, Newton Forster, although two main narrative strands (first, Newton's family, life and times and second, a foundling infant) are brought together and resolved by the end. The narrative is interspersed by frequent essay-style digressions addressed to the reader (on politics, the economy, the armed forces, slavery, domestic life, for example, and also on more minor points of interest, such as the quality and provenance of Madeira wine, the isolation of authorship, and so on). Set in various locations in England (beginning in Cumberland, moving to Liverpool, and ending in London), the narrative describes and comments on the extended Forster family, and follows Newton's (very mixed) fortunes as a merchant seaman. He is shipwrecked more than once, press-ganged, imprisoned, attacked by pirates, involved in countless skirmishes and battles at sea, and eventually takes charge of a ship for the East India Company. The resolution (and meeting of the foundling / biographical narrative strands) incorporates unexpected inheritances and consequent moves into (and marriages with) high society.

Non-standard forms are seen in 'keepers' at asylum (e.g summat, warn't, I seed, gemman). Similar forms are seen in speech of two convicts (now press-ganged seamen), Collins and Thompson. In both cases, these are sociolects rather than regional representations. Some representation of Irish English (Judy Malony). The speech of the slaves on sugar plantation in West Indies is particularly marked, and the slave women are presented as constantly mispronouncing English. There is an instance of gloss (footnote). London pensioners have some generalised non-standardness, but also some typically Cockney features