Photograph of a cheque for &,xa3;25,000 made payable to Mr Harry Grindell Matthews (1880-1941). Matthews was an inventor, best known for his claim to have invented a death ray in the 1920s. This cheque was awarded by the British government, following the outbreak of the First World War, for his invention of a remotely controlled weapon against zeppelins or unmanned vehicles. Photograph of a cheque for ??25,000 made payable to Mr Harry Grindell Matthews (1880-1941). Matthews was an inventor, best known for his claim to have invented a 'death ray' in the 1920s. This cheque was awarded by the British government, following the outbreak of the First World War, for his invention of a remotely controlled weapon against zeppelins or unmanned vehicles.