During the late 17th century, especially during the reign of Charles II, there was a burst of interest in seawater desalination in England. This was due largely to the desire of Charles II to restore England's naval prominence, weakened during civil wars and the interregnum, and to the energies and influence of Secretary of the Admiralty Samuel Pepys. Prominent among the activities was a lengthy, high-profile legal dispute between patent holders of competing desalination devices. At the height of this fracas, commemorative medals were struck off, an epic poem was written, and political strings were pulled. Robert Boyle, eminent scientist and formulator of laws relating temperature, volume, and pressure of gases, was a key figure in the fray. This article recounts these and related activities of the period when interest in seawater conversion reached the top levels of government, only to fade away as actual technical accomplishments failed to live up to hopes and expectations.