The spread of engineering authority in Britain had important social and cultural connotations for the administration of government and the power of those individuals who in the past had been identified as 'mere mechanics'. As engineering specialists gained greater personal credibility and institutional authority, their role in the design of warships and naval power had changed. Naval architects had a stake in being able to guarantee the design and construction of a safe and stable vessel, but their role in ship design transcended the calculation of displacement, freeboard and centre of gravity. A cultural history of naval architecture reveals how naval architects shaped the Royal Navy's cultures of authority, understanding of science and engineering and conceptions of naval warfare. By mapping authority we can conclude that authority was increasingly withdrawn from naval officers and politicians, who once had been empowered by their experience and social status.