 Responsibility for the lighthouses (and rights to the associated light dues) were passed to a Robert Osboldston in 1643, and then in 1715 to Greenwich Hospital.In 1730 one William Knott began a period of service as lighthouse keeper at the Lower Lighthouse.Over the next 175 years five generations of the Knott family would serve as lighthouse keepers at South Foreland, making them 'probably the longest dynasty of keepers anywhere in the world'.