The Victorian navy was not the closed community of aristocrats and sailors that historians tend to suggest. Nor was the Victorian ship a readymade object of naval power. Instead, the Victorian navy was shaped by artisans as well as aristocrats, scientists as well as sailors, and a cast of actors from parliament and the press to law and literature. The interactions between these groups of actors demonstrate that the ship did not belong to a small section of naval history but rather touches on important themes in the history of science and technology and Victorian cultural history at large. This thesis argues that Victorian ships were shaped by the concerns, curiosities and controversies of the various actors who surrounded the ship. As such the ship becomes a lens to examine issues regarding 'expertise', 'mechanics', 'power' and 'science'. This thesis traces a series of controversies through which men of science, engineers and naval architects wrestled with sailors and politicians as the ship was taken from the realm of seamanship to science. This process altered the ship in ways that were not possible without the simultaneous reordering of control and expertise within the naval community. This thesis offers a co-production framework to examine the decline of wood sail ships and the rise of iron steam ships; the weakened authority of professional sailors and the strengthened authority of engineers; and the fall of aristocratic control and the ascendency of scientific expertise in the British navy. Part I of the thesis (Experience and expertise in a Victorian institution) places naval architecture and the issue of expertise in a series of political, institutional and social contexts. Chapter 1 explores the structure and culture of decision making in the Admiralty, using pamphlets, periodicals and press reports to examine how contemporaries understood craftwork, science and material change in the Royal Navy. I specifically trace the contribution of naval architects in these debates, paying attention to the cultural authority that underpinned their arguments. These various discourses demonstrate the connections in Victorian society between administration, expertise and science - three constituent elements of the politics of naval supremacy. I conclude the chapter by examining the establishment of the Institution of Naval Architects (INA) as an expert community and the mechanisms they used to simultaneously promote their authority and mark the boundaries of their expertise. Chapter 2 further develops the identity and function of craftwork and 'rules of thumb' within the matrix of working knowledge that prevailed in Admiralty dockyards and the wider shipbuilding community. My analysis draws on scholarship in the history of science that emphasises 'production', 'practice' and 'mind/hand' dynamics in order to examine the tensions between craft, art, theory and science. Instead of focusing exclusively on the perspectives of scientists and engineers I describe the discourse that existed between them and the administrators, politicians and naval officers who were largely unsympathetic to 'theory', and administered the educational system that naval architects and engineers sought to reform. Using parliamentary debates, papers delivered to the INA and documents describing pedagogical approaches to naval architecture I explore how INA members made a space for, and educated, scientific experts within a craft culture. Part II of the thesis (Experiment and the science of naval architecture) focuses on the cultures of experiment and science in Victorian naval architecture. I examine the ideas and working practices of a group of naval architects, engineers, men of science, mathematicians and naval officers that I identity as a coherent social network. Chapter 3 uses the private papers and published works of James Robert Napier, W.J. Macquorn Rankine, John Scott Russell and William Froude to describe the nature of 'experiment' and demonstrate how knowledge of (and trust in) hydrodynamics was housed within a network of individual's reputations, social dynamics, institutions, local concerns and object meanings. Experiments in naval architecture were conceived in an array of cultural and intellectual contexts. Chapter 4 specifically focuses on Froude's contributions as both a member of a social network of naval architects and as a Victorian influenced by the culture of intellectual and religious doubt. I explore Froude's lengthy correspondence with John Newman, leader of the Oxford Movement and convert to Roman Catholicism, to emphasise the connections between scientific method and Victorian culture. I then turn to a series of debates between Froude and members of the INA to demonstrate how themes of 'doubt' and 'certainty' informed Froude's approach to hydrodynamics. Chapter 5 concludes my analysis of the culture of experiment and suggests that British naval architects sought to reconfigure the ship as an object of science, specifically in relation to the trends within Victorian science toward model experiments, mechanical science and precision measurement. I trace the culture in which Froude's test tank took shape, broadening my analysis from chapter 4 by examining discussions in the INA, the scientific community and the British Admiralty. The chapter begins with an examination of the socio-cultural politics of the Admiralty's decision to fund Froude's test tank and model experiments, shedding further light on the culture of Admiralty decision making. The chapter concludes with a discussion of craft and science, drawing in issues discussed in chapter 2 to examine the mind/hand dynamics at work in Froude's experimental practices. Part III of the thesis (Experiment, experience and expertise in the navy) returns to the broader perspectives discussed in Part I to explore how the skills possessed by naval architects were understood and promoted in the Victorian naval community and governmental machinery. Chapter 6 follows members of the British social network of naval architects through their disputes with naval officers and administrators over the use of science in making ships. I specifically pay attention to the discourses of naval officers in pamphlets, Victorian periodicals and the press to examine the authority of the sailor as ship designer and expert of ship behaviour. Through a discussion of how sailors understood 'science' I locate the controversies surrounding H. M. S. Captain and H. M. S. Devastation within a dispute over expertise. Chapter 7 draws my discussion of the culture of expertise to a close. I explore how naval architects and officers understood and expressed these changes, paying particular attention to the functions of experiment and experience, the nature of mechanical power and the establishment of a class of scientific managers within the Admiralty shipyards. I emphasise how these processes took place in relations to the decline in the authority of naval officers and their skills to judge ship behaviour, the transition in the shipbuilding industry from a craft orientated practice to a mechanical one, and the changing nature of Victorian expertise.