An radiometer The Savoy theatre music group

music group

28th June 1990

The George Tavern and shop fronts

showing the injured Cavalier discovered by Puritans

photographer & portrait painter

An radiometer The Savoy theatre music groupA radiometer with aluminium vanes. An instrument designed for measuring the mechanical effect of radiant energy. Mounted in a partial vacuum, the central rotor spins when the vanes are exposed to light. Chemist William Crookes (1832 1919) initially believed the vanes with black surfaces were pushed around by pressure from light radiation. This was incorrect and other theories were put forward. It was not until 1879 that Osborne Reynolds suggested the