1 sept 1950 año - Konrad Zuse leased his Z4 machine to the ETH Zurich for five years.
Z4 was a relay-based machine.
The corresponding contract was signed in the fall of 1949,
and the machine reassembled in Zurich after its arrival in July 1950.
The Z4 was replaced by ERMETH, a computer developed at the
ETH in Switzerland from 1953 to 1956, one of the first
electronic computers on the European continent.