 In 1926 he employed his electronics skills to construct an amplifier using thermionic valves (vacuum tubes) for very small electrical currents.It was realized that such devices could be used in the detection and counting of Alpha particles in the nuclear disintegration experiments then being undertaken by Rutherford, who encouraged him to devote his attention to the construction of a reliable valve amplifier and methods of registering and counting particles.There followed a series of brilliant contributions to the armamentarium of nuclear physics.