'Bidston Lighthouse and Signals', c 1771.
© Science Museum / Science & Society Picture Library
Illustrated plate taken from William Hutchinson's 'A Treatise on Naval Architecture' (1794). The original Bidston Lighthouse was built on Bidston Hill, the Wirral, Merseyside, in 1771. Hutchinson designed this reflector measuring over 4 metres in diameter for the lighthouse. It was made of silvered glas and lit by an oil light. Hutchinson had experimented with signal reflectors for several years, erecting a reflecting mirror at the Bidston signal station as early as 1763, but this represents the first illustration of a lighthouse signal reflector.