Austrian IT engineer Gustav Tauschek invented the first widely used computer memory, called drum memory. While he created drum memory in 1932, it took more than 20 years for the technology to be generally adopted. The decade following the invention of drum memory also saw several other, albeit short-lived memory ideas. For example, Konrad Zuse used mechanical sliding metal memory in his Z3 device, considered to be the first Turing-complete computer. In 1939, Helmut Schreyer, who worked with Zuse on the Z3, invented neon lamp-based memory. In 1942, the Atanasoff-Berry Computer combined capacitors mounted on two revolving drums as well as punch cards as memory solution. The famed ENIAC introduced wire delay line memory built from mercury and nickel. By the 1950s, drum memory dominated early computers with delay lines and Williams-Kilburn tube-based memory (developed in 1947, patent #2,951,176), which used a cathode ray tube to store data, being used as alternatives.