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photographer & portrait painter
matters had not improved in Ireland since
designed by Robert Smirke
28th June 1990
Launch of HMS 'Royal Albert'
An radiometer The Savoy theatre photographer & portrait painterA 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
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