Smollett's use of life and scenes in the British navy in the early 1740's in his first novel has long been recognized as an original and important contribution to the materials of English fiction. Chapters 24–38 of Roderick Random with their abundant detail, revealing so graphically the brutalities, disease, and official incompetence involved in the conduct of naval affairs in the expedition to Carthagena 1740–41, have not only impressed Smollett's critics but have offered a firm point of departure for the conjectures of his biographers. Yet although these chapters are successful as realistic art, and suggestive in their biographical implications, there always arises the difficult question of how much of this vivid writing is historical fact and how much is fiction. This question must be the concern of critics in determining Smollett's method in the selection of his materials, and it is central to his biography.