Thermionic Valve, John Fleming WHAT:Thermionic ValveWHERE:UK LOCATION:Accreditation in progressWHEN:1904 WHO:John Ambrose Fleming DETAILS:Accreditation in progress LINKS: Accreditation in progress To register as a World Origin Site, large or small, simply supply your Claim together with its Justification to the website for inclusion in this new Global Database.REGISTER HEREOther World Origin Sites Television Broadcast, BBC Photography, Henry Fox Talbot Underground Railway, Metropolitan Railway Gravity, Sir Isaac Newton Check us out on Social Media Martin Wilkie2024-01-20T14:07:50+00:00