In this article, Mike Breward looks at the use of Muster rolls on ships, noting what their purpose was and why they are so important. "Muster Rolls, listing ship's crews by name together with their service details, became a legal requirement on ship owners by an Act of Parliament in 1747. Their original purpose was to record monies paid into the 'hospital fund', a levy from seamen's wages for a relief fund for the injured and the provision of payments to widows and families of deceased sailors".