Prof. Dr. Horst Zuse framed the story of his father's life in the overall story of supercomputing in the United States, the United Kingdom and Germany. He started out with the Mark I and the ENIAC, both built in 1944 and compared these machines with the Konrad Zuse achievements, the Z1, Z3 and Z4 that were developed between 1936 and 1945.
Horst Zuse, the son of Konrad, was born on November 17, 1945 in Bavaria, Germany and became the eyewitness of the development of computers from 1949 at the age of four. The first machines were built taking into account issues such as information retrieval, software measurement and computer architecture.
Howard Aiken, developer of the Mark I in 1944, was approached by the son of Watson. Watson worked for IBM and convinced Aiken to build the Mark I. The Mark I was sponsored by IBM and his features included
72 decimal Hollerith-calculators/accumulators, 800.000 pieces, 35 tons, 750 km calbes, and 15.000 relays.
It was a gift of IBM to the Harvard University.
The Mark I had a memory for 23 decimal digits, 20 numbers and it was controlled by punch tapes. At "The Bane" on August 7, 1944, Aiken however did not mention IBM and because of this, IBM did not want to come to Harvard University.
The ENIAC was also built in 1944. It took only 1 hour to convince the American Army in 1941 to build the ENIAC with 20.000 vacuum tubes. The girls of the ENIAC operated it.
The first computer bug was discovered on 9 September in 1946 by Grace Hopper. It was a fly in the contact of a relay of the MARK I. Grace Hopper later on became the mother of COBOL.
Konrad Zuse was born in 1910 and died in 1995. At 16, he was drawing cartoons in Hoyerswerda and there was nothing in sight about computing building yet. He studied machine construction in Berlin from 1929 to 1934 and architecture at the Polytechnical Highschool in Berlin Charlottenburg but it was boring for him. As a living he made advertising posters for a company but his thoughts were still not on computing.
Eventually, he went back to the university to study engineering and that changed his life to computers. He started in 1935, long before the American machines, in the living room of his parents. The first design was
For the Z1, Z3 and Z4 Zuse machines, he used binary floating-point numbers. Consider the number 1212,3411 which can be written differently to become the mantissa.
The construction of the Z1 happened in 1936-1938. In 1937 the memory was finished with Boolean switching logic and a memory of 64 words with 22 bits. The reconstruction of the Z1 was done in 1987-1989. Today, we are familiar with the measurement of floating point numbers but the Z1 has a speed of 1 hertz.
Prof. Dr. Horst Zue showed how the calculation with metal sheets is possible:
The Z3 machine was ready on 12 May, 1941 and had two memory cupboards and one arithmetic unit. It came out without any sensation and no press at all. It was functional in all components and became the
first functional programmable computer.
All calculations were done with repeated additions: one bit for each relay and 22 bits for one word - floating point number. The Z3 had a speed of 5 hertz. The input device had decimal floating-point numbers. It took three steps to make a floating point addition but the Mark I was not faster!
The Z4 was built in Berlin between 1942 and 1945. Konrad Zuse could escape from Berlin at the end of the war with the Z4 computer. How was the situation in 1945? Prof. Dr. Horst Zuse told the audience that the Z2 was destroyed in 1942. The Z4 was not destroyed, and neither was the S1.
In the United Kingdom the 12 COLOSSUS was built as a special computer for decoding the codes of the Germans.
Konrad Zuse came to Hinterstein in 1945-1946 in Hotel Steinadler. In a cottage the Z4 computer was hidden and encased with hay. In 1945-1946, it was the only working computer in Europe.
In 1949, Professor Eduard Stiefel from ETH Zürich came to Hopferau because he had heard of the Z4.
Stiefel was very impressed. He wanted the Z4 to calculate the solution of a differential-equation and Konrad Zuse writes the programme for it.
The Zuse KG company was founded on November 8 in 1949. The improvement of the Z4 was the first task of the Zuse KG. On July 12, 1950 the Z4 was delivered and rented to ETH Zürich. It had a memory of 32 bits and a programme development support feature, a kind of symbolic programming.
The first delivery of a computer in Germany by Zuse KG was the Z5, ordered by LEITZ. In 1957, there was an order by Remington Band. The Zuse KG company expanded enormously between 1949 and 1969. The Z22 became the most famous machine in Germany in 1957.
In 1990 there was an acknowledgement from IBM of Konrad Zuse in a small booklet and Bill Gates met Konrad Zuse in 1995. However, the relationship between Konrad Zuse and the PC was not always harmonious, as shown by son Zuse on a funny picture of father Zuse, making a face at the PC.