Harry Grindell Matthews (1880-1941). Invented a remote-controlled selenium-powered anti-zeppelin weapon. Invented an aerial torpedo. Invented the first talking picture. Invented the "luminaphone" and "sky projector." Nick-named "Death-Ray" because of something he claimed to have invented (the patent was for a device capable of "remote projection of invisible high frequency electricity"). Lived in the lower Swansea Valley in a mountain lab surrounded by barbed wire and searchlights and which had its own private airstrip.
Harry "Death-Ray" Matthews, ladies and gentlemen.
Why am I suddenly thinking of Caractacus Potts?
On a different note, can't help but read about Reginald Victor Jones on the Wikipedia and notice that whoever wrote the article decided not to comment on Jones's reputation as a practical joker...?