William Williams (1727–1791) wrote a novel entitledMr. Penrose: The Journal of Penrose, Seamanabout an English sailor marooned on the Caribbean coast of Nicaragua, partly based on the author’s own experience. Internal linguistic evidence confirms that the castaway’s contact was with the Rama and Miskito Indians of this area. The novel’s 350 printed pages are in the formal English of the times, but also include dialogue in the local vernacular English that was still undergoing creolization. It includes words not only from Rama and Miskito, but also Spanish and African languages and phrases suggesting convergence with modern English Creole structures (“Harry wassick,sick”). This article uses lexical and morphosyntactic data from the 18th-century manuscript to cast light on the origin of synchronic features of Miskito Coast Creole English.